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Maroofian R, Sarraf P, O'Brien TJ, Kamel M, Cakar A, Elkhateeb N, Lau T, Patil SJ, Record CJ, Horga A, Essid M, Selim L, Benrhouma H, Ben Younes T, Zifarelli G, Pagnamenta AT, Bauer P, Khundadze M, Mirecki A, Kamel SM, Elmonem MA, Ghayoor Karimiani E, Jamshidi Y, Offiah AC, Rossor AM, Youssef-Turki IB, Hübner CA, Munot P, Reilly MM, Brown AEX, Nagy S, Houlden H. Reticulon 2 deficiency results in an autosomal recessive distal motor neuropathy with lower limb spasticity. Brain 2024:awae091. [PMID: 38527963 DOI: 10.1093/brain/awae091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 01/30/2024] [Accepted: 02/25/2024] [Indexed: 03/27/2024] Open
Abstract
Heterozygous RTN2 variants have been previously identified in a limited cohort of families affected by autosomal dominant spastic paraplegia (SPG12-OMIM:604805) with a variable age of onset. Nevertheless, the definitive validity of SPG12 remains to be confidently confirmed due to scarcity of supporting evidence. In our study, we identified and validated seven novel or ultra-rare homozygous loss-of-function RTN2 variants in 14 individuals from seven consanguineous families with distal hereditary motor neuropathy (dHMN) using exome, genome and Sanger sequencing coupled with deep-phenotyping. All affected individuals (seven males and seven females, aged 9-50 years) exhibited weakness in the distal upper and lower limbs, lower limb spasticity, hyperreflexia, with an onset in the first decade of life. Nerve conduction studies revealed axonal motor neuropathy with neurogenic changes in the electromyography. Despite a slowly progressive disease course, all patients remained ambulatory over a mean disease duration of 19.71 ± 13.70 years. Characterisation of C. elegans RTN2 homolog loss-of-function variants demonstrated morphological and behavioural differences compared to the parental strain. Treatment of the mutant with an endoplasmic/sarcoplasmic reticulum Ca2+ reuptake inhibitor (2,5-di-tert-butylhydroquinone) rescued key phenotypic differences, suggesting a potential therapeutic benefit for RTN2-disorder. Despite Reticulon-2 being an endoplasmic reticulum (ER)-resident membrane shaping protein, our analysis of patient fibroblast cells did not find significant alterations in ER structure or the response to ER stress. Our findings delineate a distinct form of autosomal recessive dHMN with pyramidal features associated with Reticulon-2 deficiency. This phenotype shares similarities with SIGMAR1-related dHMN, and Silver-like syndromes, providing valuable insights into the clinical spectrum and potential therapeutic strategies for RTN2-related dHMN.
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Affiliation(s)
- Reza Maroofian
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Payam Sarraf
- Department of Neuromuscular Diseases, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, 1416753955, Iran
- Department of Neurology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, 1416753955, Iran
| | - Thomas J O'Brien
- Institute of Clinical Sciences, Imperial College London, London, SW7 2AZ, UK
- MRC Laboratory of Medical Sciences, London, W12 0HS, UK
| | - Mona Kamel
- Department of Pediatrics, Neurology and Metabolic Division, Kasr Alainy Faculty of Medicine, Cairo University, Cairo, 4240310, Egypt
| | - Arman Cakar
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- Neuromuscular Unit, Istanbul University, Istanbul Faculty of Medicine, Istanbul, 34093, Turkey
| | - Nour Elkhateeb
- Department of Clinical Genetics, Cambridge University Hospitals NHS Foundation Trust, Cambridge, CB2 0QQ, UK
| | - Tracy Lau
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Siddaramappa Jagdish Patil
- Division of Medical Genetics, Mazumdar Shaw Medical Center, Narayana Hrudayalaya Hospital, Bangalore, 560099, India
| | - Christopher J Record
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Alejandro Horga
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Miriam Essid
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, 1007, Tunisia
| | - Laila Selim
- Department of Pediatrics, Neurology and Metabolic Division, Kasr Alainy Faculty of Medicine, Cairo University, Cairo, 4240310, Egypt
| | - Hanene Benrhouma
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, 1007, Tunisia
| | - Thouraya Ben Younes
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, 1007, Tunisia
| | | | - Alistair T Pagnamenta
- NIHR Oxford Biomedical Research Centre, Centre for Human Genetics, University of Oxford, Oxford, OX3 9DU, UK
| | | | - Mukhran Khundadze
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, 07747, Germany
| | - Andrea Mirecki
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, 07747, Germany
| | | | - Mohamed A Elmonem
- Department of Clinical and Chemical Pathology, Kasr Alainy Faculty of Medicine, Cairo University, Cairo, 12613, Egypt
| | - Ehsan Ghayoor Karimiani
- Molecular and Clinical Sciences Institute, St. George's, University of London, SW17 0RE, UK
- Innovative Medical Research Center, Mashhad Branch, Islamic Azad University, Mashhad, 9187147578, Iran
| | - Yalda Jamshidi
- Molecular and Clinical Sciences Institute, St. George's, University of London, SW17 0RE, UK
| | - Amaka C Offiah
- Division of Clinical Medicine, School of Medicine & Population Health, University of Sheffield, Sheffield, S10 2RX, UK
| | - Alexander M Rossor
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Ilhem Ben Youssef-Turki
- LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, 1007, Tunisia
| | - Christian A Hübner
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, 07747, Germany
- Center for Rare Diseases, Jena University Hospital, Friedrich Schiller Universität, Jena, 07747, Germany
| | - Pinki Munot
- Dubowitz Neuromuscular Centre, Great Ormond Street Hospital NHS Trust, London, WC1N 3JH, UK
| | - Mary M Reilly
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - André E X Brown
- Institute of Clinical Sciences, Imperial College London, London, SW7 2AZ, UK
- MRC Laboratory of Medical Sciences, London, W12 0HS, UK
| | - Sara Nagy
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- Department of Neurology, University Hospital Basel, University of Basel, Basel, 4031, Switzerland
| | - Henry Houlden
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
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2
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Chelban V, Aksnes H, Maroofian R, LaMonica LC, Seabra L, Siggervåg A, Devic P, Shamseldin HE, Vandrovcova J, Murphy D, Richard AC, Quenez O, Bonnevalle A, Zanetti MN, Kaiyrzhanov R, Salpietro V, Efthymiou S, Schottlaender LV, Morsy H, Scardamaglia A, Tariq A, Pagnamenta AT, Pennavaria A, Krogstad LS, Bekkelund ÅK, Caiella A, Glomnes N, Brønstad KM, Tury S, Moreno De Luca A, Boland-Auge A, Olaso R, Deleuze JF, Anheim M, Cretin B, Vona B, Alajlan F, Abdulwahab F, Battini JL, İpek R, Bauer P, Zifarelli G, Gungor S, Kurul SH, Lochmuller H, Da'as SI, Fakhro KA, Gómez-Pascual A, Botía JA, Wood NW, Horvath R, Ernst AM, Rothman JE, McEntagart M, Crow YJ, Alkuraya FS, Nicolas G, Arnesen T, Houlden H. Biallelic NAA60 variants with impaired n-terminal acetylation capacity cause autosomal recessive primary familial brain calcifications. Nat Commun 2024; 15:2269. [PMID: 38480682 PMCID: PMC10937998 DOI: 10.1038/s41467-024-46354-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 02/23/2024] [Indexed: 03/17/2024] Open
Abstract
Primary familial brain calcification (PFBC) is characterized by calcium deposition in the brain, causing progressive movement disorders, psychiatric symptoms, and cognitive decline. PFBC is a heterogeneous disorder currently linked to variants in six different genes, but most patients remain genetically undiagnosed. Here, we identify biallelic NAA60 variants in ten individuals from seven families with autosomal recessive PFBC. The NAA60 variants lead to loss-of-function with lack of protein N-terminal (Nt)-acetylation activity. We show that the phosphate importer SLC20A2 is a substrate of NAA60 in vitro. In cells, loss of NAA60 caused reduced surface levels of SLC20A2 and a reduction in extracellular phosphate uptake. This study establishes NAA60 as a causal gene for PFBC, provides a possible biochemical explanation of its disease-causing mechanisms and underscores NAA60-mediated Nt-acetylation of transmembrane proteins as a fundamental process for healthy neurobiological functioning.
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Affiliation(s)
- Viorica Chelban
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK.
- Neurobiology and Medical Genetics Laboratory, "Nicolae Testemitanu" State University of Medicine and Pharmacy, 165, Stefan cel Mare si Sfant Boulevard, MD, 2004, Chisinau, Republic of Moldova.
| | - Henriette Aksnes
- Department of Biomedicine, University of Bergen, Bergen, Norway.
| | - Reza Maroofian
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Lauren C LaMonica
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Luis Seabra
- Université Paris Cité, Imagine Institute, Laboratory of Neurogenetics and Neuroinflammation, INSERM UMR 1163, Paris, France
| | | | - Perrine Devic
- Hospices Civils de Lyon, Groupement Hospitalier Sud, Service d'Explorations Fonctionnelles Neurologiques, Lyon, France
| | - Hanan E Shamseldin
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Jana Vandrovcova
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - David Murphy
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Anne-Claire Richard
- Univ Rouen Normandie, Inserm U1245, CHU Rouen, Department of Genetics and CNRMAJ, F-76000, Rouen, France
| | - Olivier Quenez
- Univ Rouen Normandie, Inserm U1245, CHU Rouen, Department of Genetics and CNRMAJ, F-76000, Rouen, France
| | - Antoine Bonnevalle
- Univ Rouen Normandie, Inserm U1245, CHU Rouen, Department of Genetics and CNRMAJ, F-76000, Rouen, France
| | - M Natalia Zanetti
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Rauan Kaiyrzhanov
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- South Kazakhstan Medical Academy Shymkent, Shymkent, 160019, Kazakhstan
| | - Vincenzo Salpietro
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Stephanie Efthymiou
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Lucia V Schottlaender
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- Instituto de Investigaciones en Medicina Traslacional (IIMT), CONICET-Universidad Austral, Av. Juan Domingo Perón 1500, B1629AHJ, Pilar, Argentina
- Instituto de medicina genómica (IMeG), Hospital Universitario Austral, Universidad Austral, Av. Juan Domingo Perón 1500, B1629AHJ, Pilar, Argentina
| | - Heba Morsy
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- Department of Human Genetics, Medical Research Institute, Alexandria University, Alexandria, Egypt
| | - Annarita Scardamaglia
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Ambreen Tariq
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Alistair T Pagnamenta
- Oxford NIHR Biomedical Research Centre, Wellcome Centre for Human Genetics, Oxford, United Kingdom
| | - Ajia Pennavaria
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Liv S Krogstad
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Åse K Bekkelund
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Alessia Caiella
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Nina Glomnes
- Department of Biomedicine, University of Bergen, Bergen, Norway
- Department of Clinical Science, University of Bergen, 5020, Bergen, Norway
| | | | - Sandrine Tury
- Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier, CNRS, Montpellier, France
| | - Andrés Moreno De Luca
- Department of Radiology, Autism & Developmental Medicine Institute, Geisinger, Lewisburg, PA, USA
- Department of Radiology, Neuroradiology Section, Kingston Health Sciences Centre, Queen's University Faculty of Health Sciences, Kingston, Ontario, Canada
| | - Anne Boland-Auge
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine (CNRGH), 91057, Evry, France
| | - Robert Olaso
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine (CNRGH), 91057, Evry, France
| | - Jean-François Deleuze
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine (CNRGH), 91057, Evry, France
| | - Mathieu Anheim
- Neurology Department, Strasbourg University Hospital, Strasbourg, France
- Strasbourg Federation of Translational Medicine (FMTS), Strasbourg University, Strasbourg, France
- INSERM-U964; CNRS-UMR7104, University of Strasbourg, Illkirch-Graffenstaden, France
| | - Benjamin Cretin
- Neurology Department, Strasbourg University Hospital, Strasbourg, France
- Strasbourg Federation of Translational Medicine (FMTS), Strasbourg University, Strasbourg, France
- INSERM-U964; CNRS-UMR7104, University of Strasbourg, Illkirch-Graffenstaden, France
| | - Barbara Vona
- Institute of Human Genetics, University Medical Center Göttingen, 37073, Göttingen, Germany
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075, Göttingen, Germany
| | - Fahad Alajlan
- Department of Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Firdous Abdulwahab
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Jean-Luc Battini
- Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier, CNRS, Montpellier, France
| | - Rojan İpek
- Paediatric Neurology, Faculty of Medicine, Dicle University, Diyarbakır, Turkey
| | - Peter Bauer
- Centogene GmbH, Am Strande 7, 18055, Rostock, Germany
| | | | - Serdal Gungor
- Inonu University, Faculty of Medicine, Turgut Ozal Research Center, Department of Pediatrics, Division of Pediatric Neurology, Malatya, Turkey
| | - Semra Hiz Kurul
- Dokuz Eylul University, School of Medicine, Department of Paediatric Neurology, Izmir, Turkey
| | - Hanns Lochmuller
- Children's Hospital of Eastern Ontario Research Institute and Division of Neurology, Department of Medicine, The Ottawa Hospital, Ottawa, Canada
- Brain and Mind Research Institute, University of Ottawa, Ottawa, Canada
- Department of Neuropediatrics and Muscle Disorders, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Sahar I Da'as
- Department of Human Genetics, Sidra Medicine, Doha, Qatar
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar
| | - Khalid A Fakhro
- Department of Human Genetics, Sidra Medicine, Doha, Qatar
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar
- Weill Cornell Medical College, Doha, Qatar
| | - Alicia Gómez-Pascual
- Department of Information and Communications Engineering, University of Murcia, Campus Espinardo, 30100, Murcia, Spain
| | - Juan A Botía
- Department of Information and Communications Engineering, University of Murcia, Campus Espinardo, 30100, Murcia, Spain
| | - Nicholas W Wood
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- Neurogenetics Laboratory, The National Hospital for Neurology and Neurosurgery, London, WC1N 3BG, UK
| | - Rita Horvath
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Andreas M Ernst
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - James E Rothman
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Meriel McEntagart
- Medical Genetics Department, St George's University Hospitals, London, SWI7 0RE, UK
| | - Yanick J Crow
- Université Paris Cité, Imagine Institute, Laboratory of Neurogenetics and Neuroinflammation, INSERM UMR 1163, Paris, France
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK
| | - Fowzan S Alkuraya
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Gaël Nicolas
- Univ Rouen Normandie, Inserm U1245, CHU Rouen, Department of Genetics and CNRMAJ, F-76000, Rouen, France
| | - Thomas Arnesen
- Department of Biomedicine, University of Bergen, Bergen, Norway.
- Department of Surgery, Haukeland University Hospital, Bergen, Norway.
| | - Henry Houlden
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK.
- Neurogenetics Laboratory, The National Hospital for Neurology and Neurosurgery, London, WC1N 3BG, UK.
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Dharmadhikari AV, Abad MA, Khan S, Maroofian R, Sands TT, Ullah F, Samejima I, Wear MA, Moore KE, Kondakova E, Mitina N, Schaub T, Lee GK, Umandap CH, Berger SM, Iglesias AD, Popp B, Jamra RA, Gabriel H, Rentas S, Rippert AL, Izumi K, Conlin LK, Koboldt DC, Mosher TM, Hickey SE, Albert DVF, Norwood H, Lewanda AF, Dai H, Liu P, Mitani T, Marafi D, Pehlivan D, Posey JE, Lippa N, Vena N, Heinzen EL, Goldstein DB, Mignot C, de Sainte Agathe JM, Al-Sannaa NA, Zamani M, Sadeghian S, Azizimalamiri R, Seifia T, Zaki MS, Abdel-Salam GMH, Abdel-Hamid M, Alabdi L, Alkuraya FS, Dawoud H, Lofty A, Bauer P, Zifarelli G, Afzal E, Zafar F, Efthymiou S, Gossett D, Towne MC, Yeneabat R, Wontakal SN, Aggarwal VS, Rosenfeld JA, Tarabykin V, Ohta S, Lupski JR, Houlden H, Earnshaw WC, Davis EE, Jeyaprakash AA, Liao J. RNA methyltransferase SPOUT1/CENP-32 links mitotic spindle organization with the neurodevelopmental disorder SpADMiSS. medRxiv 2024:2024.01.09.23300329. [PMID: 38260255 PMCID: PMC10802637 DOI: 10.1101/2024.01.09.23300329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
SPOUT1/CENP-32 encodes a putative SPOUT RNA methyltransferase previously identified as a mitotic chromosome associated protein. SPOUT1/CENP-32 depletion leads to centrosome detachment from the spindle poles and chromosome misalignment. Aided by gene matching platforms, we identified 24 individuals with neurodevelopmental delays from 18 families with bi-allelic variants in SPOUT1/CENP-32 detected by exome/genome sequencing. Zebrafish spout1/cenp-32 mutants showed reduction in larval head size with concomitant apoptosis likely associated with altered cell cycle progression. In vivo complementation assays in zebrafish indicated that SPOUT1/CENP-32 missense variants identified in humans are pathogenic. Crystal structure analysis of SPOUT1/CENP-32 revealed that most disease-associated missense variants mapped to the catalytic domain. Additionally, SPOUT1/CENP-32 recurrent missense variants had reduced methyltransferase activity in vitro and compromised centrosome tethering to the spindle poles in human cells. Thus, SPOUT1/CENP-32 pathogenic variants cause an autosomal recessive neurodevelopmental disorder: SpADMiSS ( SPOUT1 Associated Development delay Microcephaly Seizures Short stature) underpinned by mitotic spindle organization defects and consequent chromosome segregation errors.
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4
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De Pace R, Maroofian R, Paimboeuf A, Zamani M, Zaki MS, Sadeghian S, Azizimalamiri R, Galehdari H, Zeighami J, Williamson CD, Fleming E, Zhou D, Gannon JL, Thiffault I, Roze E, Suri M, Zifarelli G, Bauer P, Houlden H, Severino M, Patten SA, Farrow E, Bonifacino JS. Biallelic BORCS8 variants cause an infantile-onset neurodegenerative disorder with altered lysosome dynamics. Brain 2023:awad427. [PMID: 38128568 DOI: 10.1093/brain/awad427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 09/30/2023] [Accepted: 12/02/2023] [Indexed: 12/23/2023] Open
Abstract
BLOC-One-Related Complex (BORC) is a multiprotein complex composed of eight subunits named BORCS1-8. BORC associates with the cytosolic face of lysosomes, where it sequentially recruits the small GTPase ARL8 and kinesin-1 and -3 microtubule motors to promote anterograde transport of lysosomes toward the peripheral cytoplasm in non-neuronal cells and the distal axon in neurons. The physiological and pathological importance of BORC in humans, however, remains to be determined. Here, we report the identification of compound heterozygous variants [missense c.85T > C (p.Ser29Pro) and frameshift c.71-75dupTGGCC (p.Asn26Trpfs*51)] and homozygous variants [missense c.196A > C (p.Thr66Pro) and c.124T > C (p.Ser42Pro)] in BORCS8 in five children with a severe early-infantile neurodegenerative disorder from three unrelated families. The children exhibit global developmental delay, severe-to-profound intellectual disability, hypotonia, limb spasticity, muscle wasting, dysmorphic facies, optic atrophy, leuko-axonopathy with hypomyelination, and neurodegenerative features with prevalent supratentorial involvement. Cellular studies using a heterologous transfection system show that the BORCS8 missense variants p.Ser29Pro, p.Ser42Pro and p.Thr66Pro are expressed at normal levels but exhibit reduced assembly with other BORC subunits and reduced ability to drive lysosome distribution toward the cell periphery. The BORCS8 frameshift variant p.Asn26Trpfs*51, on the other hand, is expressed at lower levels and is completely incapable of assembling with other BORC subunits and promoting lysosome distribution toward the cell periphery. Therefore, all the BORCS8 variants are partial or total loss-of-function alleles and are thus likely pathogenic. Knockout of the orthologous borcs8 in zebrafish causes decreased brain and eye size, neuromuscular anomalies and impaired locomotion, recapitulating some of the key traits of the human disease. These findings thus identify BORCS8 as a novel genetic locus for an early-infantile neurodegenerative disorder and highlight the critical importance of BORC and lysosome dynamics for the development and function of the central nervous system.
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Affiliation(s)
- Raffaella De Pace
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shiver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Reza Maroofian
- UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Adeline Paimboeuf
- INRS - Centre Armand Frappier Santé Biotechnologie, Laval, QC H7 V 1B7, Canada
| | - Mina Zamani
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, 83151-61355, Iran
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Kianpars, Ahvaz, 61556-89467, Iran
| | - Maha S Zaki
- Human Genetics and Genome Research Division, Clinical Genetics Department, National Research Centre, Cairo, 12622, Egypt
| | - Saeid Sadeghian
- Department of Pediatric Neurology, Golestan Medical, Educational, and Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, 61357-33184, Iran
| | - Reza Azizimalamiri
- Department of Pediatric Neurology, Golestan Medical, Educational, and Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, 61357-33184, Iran
| | - Hamid Galehdari
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, 83151-61355, Iran
| | - Jawaher Zeighami
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Kianpars, Ahvaz, 61556-89467, Iran
| | - Chad D Williamson
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shiver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Emily Fleming
- Department of Genetics, Children's Mercy Kansas City, Kansas City, MO 64108, USA
| | - Dihong Zhou
- Department of Genetics, Children's Mercy Kansas City, Kansas City, MO 64108, USA
- Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108, USA
| | - Jennifer L Gannon
- Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108, USA
- Division of Clinical Genetics, Children's Mercy Kansas City, Kansas City, MO 64108, USA
| | - Isabelle Thiffault
- Department of Genetics, Children's Mercy Kansas City, Kansas City, MO 64108, USA
- Department of Pathology, Children's Mercy Kansas City, Kansas City, MO 64108, USA
| | - Emmanuel Roze
- Sorbonne Université, CNRS, INSERM, Institut du Cerveau (ICM), and Assistance Publique-Hôpitaux de Paris, Hôpital de la Pitié-Salpêtrière, Paris, 75013, France
| | - Mohnish Suri
- Nottingham Clinical Genetics Service, Nottingham University Hospitals NHS Trust, City Hospital Campus, Nottingham, NG5 1PB, UK
| | | | - Peter Bauer
- CENTOGENE GmbH, Am Strande 7, 18055 Rostock, Germany
| | - Henry Houlden
- UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | | | - Shunmoogum A Patten
- INRS - Centre Armand Frappier Santé Biotechnologie, Laval, QC H7 V 1B7, Canada
- Departement de Neurosciences, Université de Montréal, QC H3C 3J7, Canada
| | - Emily Farrow
- Department of Genetics, Children's Mercy Kansas City, Kansas City, MO 64108, USA
- Genomic Medicine Center, Children's Mercy Kansas City, Kansas City, MO 64108, USA
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shiver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
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5
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Engal E, Oja KT, Maroofian R, Geminder O, Le TL, Marzin P, Guimier A, Mor E, Zvi N, Elefant N, Zaki MS, Gleeson JG, Muru K, Pajusalu S, Wojcik MH, Pachat D, Elmaksoud MA, Chan Jeong W, Lee H, Bauer P, Zifarelli G, Houlden H, Daana M, Elpeleg O, Amiel J, Lyonnet S, Gordon CT, Harel T, Õunap K, Salton M, Mor-Shaked H. Bi-allelic loss-of-function variants in WBP4, encoding a spliceosome protein, result in a variable neurodevelopmental syndrome. Am J Hum Genet 2023; 110:2112-2119. [PMID: 37963460 PMCID: PMC10716347 DOI: 10.1016/j.ajhg.2023.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/25/2023] [Accepted: 10/25/2023] [Indexed: 11/16/2023] Open
Abstract
Over two dozen spliceosome proteins are involved in human diseases, also referred to as spliceosomopathies. WW domain-binding protein 4 (WBP4) is part of the early spliceosomal complex and has not been previously associated with human pathologies in the Online Mendelian Inheritance in Man (OMIM) database. Through GeneMatcher, we identified ten individuals from eight families with a severe neurodevelopmental syndrome featuring variable manifestations. Clinical manifestations included hypotonia, global developmental delay, severe intellectual disability, brain abnormalities, musculoskeletal, and gastrointestinal abnormalities. Genetic analysis revealed five different homozygous loss-of-function variants in WBP4. Immunoblotting on fibroblasts from two affected individuals with different genetic variants demonstrated a complete loss of protein, and RNA sequencing analysis uncovered shared abnormal splicing patterns, including in genes associated with abnormalities of the nervous system, potentially underlying the phenotypes of the probands. We conclude that bi-allelic variants in WBP4 cause a developmental disorder with variable presentations, adding to the growing list of human spliceosomopathies.
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Affiliation(s)
- Eden Engal
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel; Department of Military Medicine and "Tzameret," Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Kaisa Teele Oja
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia; Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Reza Maroofian
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Ophir Geminder
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel; Department of Military Medicine and "Tzameret," Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Thuy-Linh Le
- Laboratory of Embryology and Genetics of Human Malformations, Institut National de La Santé et de La Recherche Médicale (INSERM) UMR 1163, Institut Imagine and Université Paris Cité, 75015 Paris, France
| | - Pauline Marzin
- Service de Médecine Génomique des Maladies Rares, Hôpital Necker-Enfants Malades, AP-HP, 75015 Paris, France
| | - Anne Guimier
- Laboratory of Embryology and Genetics of Human Malformations, Institut National de La Santé et de La Recherche Médicale (INSERM) UMR 1163, Institut Imagine and Université Paris Cité, 75015 Paris, France; Service de Médecine Génomique des Maladies Rares, Hôpital Necker-Enfants Malades, AP-HP, 75015 Paris, France
| | - Evyatar Mor
- Department of Computer Science, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Naama Zvi
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel
| | - Naama Elefant
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel
| | - Maha S Zaki
- Department of Clinical Genetics, Human Genetics and Genome Research Institute, Cairo, Egypt
| | - Joseph G Gleeson
- Department of Neurosciences, University of California, San Diego, La Jolla, USA; Rady Children's Institute for Genomic Medicine, San Diego, La Jolla, USA
| | - Kai Muru
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia; Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Sander Pajusalu
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia; Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | | | - Divya Pachat
- Department of Medical Genetics, Aster MIMS (Malabar Institute of Medical Sciences)-Calicut, Kerala, India
| | - Marwa Abd Elmaksoud
- Neurology Unit, Department of Pediatrics, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | | | | | - Peter Bauer
- CENTOGENE GmbH, Am Strande 7, 18055 Rostock, Germany
| | | | - Henry Houlden
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Muhannad Daana
- Child Development Centers, Clalit Health Care Services, Jerusalem, Israel
| | - Orly Elpeleg
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel; Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Jeanne Amiel
- Laboratory of Embryology and Genetics of Human Malformations, Institut National de La Santé et de La Recherche Médicale (INSERM) UMR 1163, Institut Imagine and Université Paris Cité, 75015 Paris, France; Service de Médecine Génomique des Maladies Rares, Hôpital Necker-Enfants Malades, AP-HP, 75015 Paris, France
| | - Stanislas Lyonnet
- Laboratory of Embryology and Genetics of Human Malformations, Institut National de La Santé et de La Recherche Médicale (INSERM) UMR 1163, Institut Imagine and Université Paris Cité, 75015 Paris, France; Service de Médecine Génomique des Maladies Rares, Hôpital Necker-Enfants Malades, AP-HP, 75015 Paris, France
| | - Christopher T Gordon
- Laboratory of Embryology and Genetics of Human Malformations, Institut National de La Santé et de La Recherche Médicale (INSERM) UMR 1163, Institut Imagine and Université Paris Cité, 75015 Paris, France
| | - Tamar Harel
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel; Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Katrin Õunap
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia; Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Maayan Salton
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Hagar Mor-Shaked
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel; Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
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6
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Maroofian R, Kaiyrzhanov R, Cali E, Zamani M, Zaki MS, Ferla M, Tortora D, Sadeghian S, Saadi SM, Abdullah U, Karimiani EG, Efthymiou S, Yeşil G, Alavi S, Al Shamsi AM, Tajsharghi H, Abdel-Hamid MS, Saadi NW, Al Mutairi F, Alabdi L, Beetz C, Ali Z, Toosi MB, Rudnik-Schöneborn S, Babaei M, Isohanni P, Muhammad J, Khan S, Al Shalan M, Hickey SE, Marom D, Elhanan E, Kurian MA, Marafi D, Saberi A, Hamid M, Spaull R, Meng L, Lalani S, Maqbool S, Rahman F, Seeger J, Palculict TB, Lau T, Murphy D, Mencacci NE, Steindl K, Begemann A, Rauch A, Akbas S, Aslanger AD, Salpietro V, Yousaf H, Ben-Shachar S, Ejeskär K, Al Aqeel AI, High FA, Armstrong-Javors AE, Zahraei SM, Seifi T, Zeighami J, Shariati G, Sedaghat A, Asl SN, Shahrooei M, Zifarelli G, Burglen L, Ravelli C, Zschocke J, Schatz UA, Ghavideldarestani M, Kamel WA, Van Esch H, Hackenberg A, Taylor JC, Al-Gazali L, Bauer P, Gleeson JJ, Alkuraya FS, Lupski JR, Galehdari H, Azizimalamiri R, Chung WK, Baig SM, Houlden H, Severino M. Biallelic MED27 variants lead to variable ponto-cerebello-lental degeneration with movement disorders. Brain 2023; 146:5031-5043. [PMID: 37517035 PMCID: PMC10690011 DOI: 10.1093/brain/awad257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 06/29/2023] [Accepted: 07/11/2023] [Indexed: 08/01/2023] Open
Abstract
MED27 is a subunit of the Mediator multiprotein complex, which is involved in transcriptional regulation. Biallelic MED27 variants have recently been suggested to be responsible for an autosomal recessive neurodevelopmental disorder with spasticity, cataracts and cerebellar hypoplasia. We further delineate the clinical phenotype of MED27-related disease by characterizing the clinical and radiological features of 57 affected individuals from 30 unrelated families with biallelic MED27 variants. Using exome sequencing and extensive international genetic data sharing, 39 unpublished affected individuals from 18 independent families with biallelic missense variants in MED27 have been identified (29 females, mean age at last follow-up 17 ± 12.4 years, range 0.1-45). Follow-up and hitherto unreported clinical features were obtained from the published 12 families. Brain MRI scans from 34 cases were reviewed. MED27-related disease manifests as a broad phenotypic continuum ranging from developmental and epileptic-dyskinetic encephalopathy to variable neurodevelopmental disorder with movement abnormalities. It is characterized by mild to profound global developmental delay/intellectual disability (100%), bilateral cataracts (89%), infantile hypotonia (74%), microcephaly (62%), gait ataxia (63%), dystonia (61%), variably combined with epilepsy (50%), limb spasticity (51%), facial dysmorphism (38%) and death before reaching adulthood (16%). Brain MRI revealed cerebellar atrophy (100%), white matter volume loss (76.4%), pontine hypoplasia (47.2%) and basal ganglia atrophy with signal alterations (44.4%). Previously unreported 39 affected individuals had seven homozygous pathogenic missense MED27 variants, five of which were recurrent. An emerging genotype-phenotype correlation was observed. This study provides a comprehensive clinical-radiological description of MED27-related disease, establishes genotype-phenotype and clinical-radiological correlations and suggests a differential diagnosis with syndromes of cerebello-lental neurodegeneration and other subtypes of 'neuro-MEDopathies'.
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Affiliation(s)
- Reza Maroofian
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
| | - Rauan Kaiyrzhanov
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
| | - Elisa Cali
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
| | - Mina Zamani
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Kianpars, Ahvaz, Iran
- Ati Mehr Kasra Genetics Institute, Kianpars, Ahvaz, Iran
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo 12622, Egypt
| | - Matteo Ferla
- Wellcome Centre for Human Genetics, University of Oxford and Oxford NIHR Biomedical Research Centre, Oxford, OX3 7BN UK
| | - Domenico Tortora
- Neuroradiology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Saeid Sadeghian
- Department of Pediatric Neurology, Golestan Medical, Educational, and Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Saadia Maryam Saadi
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE) College, PIEAS, 44000 Faisalabad, Pakistan
| | - Uzma Abdullah
- University Institute of Biochemistry and Biotechnology, PMAS Arid Agriculture University, 46300 Rawalpindi, Pakistan
| | - Ehsan Ghayoor Karimiani
- Department of Medical Genetics, Next Generation Genetic Polyclinic, Mashhad, Iran
- Molecular and Clinical Sciences Institute, St. George’s, University of London, London SW17 0RE, UK
- Innovative Medical Research Center, Mashhad Branch, Islamic Azad University, Mashhad, Iran
| | - Stephanie Efthymiou
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
| | - Gözde Yeşil
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, 34093 Istanbul, Turkey
| | - Shahryar Alavi
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
| | - Aisha M Al Shamsi
- Genetic Division, Pediatrics Department, Tawam Hospital, Al Ain, UAE
| | - Homa Tajsharghi
- School of Health Science, Division Biomedicine and Translational Medicine, University of Skovde, SE-541 28 Skovde, Sweden
| | - Mohamed S Abdel-Hamid
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, 12622 Cairo, Egypt
| | - Nebal Waill Saadi
- College of Medicine, University of Baghdad, 10071 Baghdad, Iraq
- Children Welfare Teaching Hospital, 10071 Baghdad, Iraq
| | - Fuad Al Mutairi
- Genetics and Precision Medicine department, King Abdullah Specialized Children’s Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, 22384 Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, 22384 Riyadh, Saudi Arabia
| | - Lama Alabdi
- Department of Zoology, College of Science, King Saud University, 11421 Riyadh, Saudi Arabia
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, 12713 Riyadh, Saudi Arabia
| | | | - Zafar Ali
- Department of Cellular and Molecular Medicine, WJC PANUM, University of Copenhagen, DK-1165 Copenhagen, Denmark
- Centre for Biotechnology and Microbiology, University of Swat, Swat 19120, Pakistan
| | - Mehran Beiraghi Toosi
- Pediatric Neurology Department Pediatric Ward Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Meisam Babaei
- Department of Pediatrics, North Khorasan University of Medical Sciences, Bojnurd, Iran
| | - Pirjo Isohanni
- Research Programs Unit, Stem Cells and Metabolism, Faculty of Medicine, University of Helsinki, 00014 Helsinki, Finland
- Department of Child Neurology, Children’s Hospital, Paediatric Research Center, University of Helsinki and Helsinki University Hospital, 00014 Helsinki, Finland
| | - Jameel Muhammad
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE) College, PIEAS, 44000 Faisalabad, Pakistan
- Centre for Regenerative Medicine and Stem Cell Research, Juma Building, Aga Khan University, Karachi 74800, Pakistan
| | - Sheraz Khan
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE) College, PIEAS, 44000 Faisalabad, Pakistan
| | - Maha Al Shalan
- Genetics and Precision Medicine department, King Abdullah Specialized Children’s Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, 22384 Riyadh, Saudi Arabia
| | - Scott E Hickey
- Division of Genetic & Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43205, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| | - Daphna Marom
- Genetics Institute and Genomic Center, Tel Aviv Sourasky Medical Center, and Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Emil Elhanan
- Nephro-Genetic Clinic, Nephrology Department and Genetics Institute, Tel Aviv Medical Center, Tel Aviv 64239, Israel
| | - Manju A Kurian
- Molecular Neurosciences, Developmental Neurosciences, Zayed Centre for Research into Rare Disease in Children, UCL Great Ormond Street Institute of Child Health, London WC1N 1EH, UK
- Department of Neurology, Great Ormond Street Hospital, London WC1N 1EH, UK
| | - Dana Marafi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Pediatrics, Faculty of Medicine, Kuwait University, Safat 13110, Kuwait
| | - Alihossein Saberi
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Kianpars, Ahvaz, Iran
- Department of Medical Genetics, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Mohammad Hamid
- Department of Molecular Medicine, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Robert Spaull
- Nephro-Genetic Clinic, Nephrology Department and Genetics Institute, Tel Aviv Medical Center, Tel Aviv 64239, Israel
- Molecular Neurosciences, Developmental Neurosciences, Zayed Centre for Research into Rare Disease in Children, UCL Great Ormond Street Institute of Child Health, London WC1N 1EH, UK
| | - Linyan Meng
- Department of Neurology, Great Ormond Street Hospital, London WC1N 1EH, UK
| | - Seema Lalani
- Department of Neurology, Great Ormond Street Hospital, London WC1N 1EH, UK
| | - Shazia Maqbool
- Developmental-Behavioural Paediatrics Department, University of Child Health Sciences & The Children’s Hospital, 54000 Lahore, Pakistan
| | - Fatima Rahman
- Developmental-Behavioural Paediatrics Department, University of Child Health Sciences & The Children’s Hospital, 54000 Lahore, Pakistan
| | - Jürgen Seeger
- Center for Social Pediatrics and Epilepsy Outpatient Clinic Frankfurt Mitte, 60316 Frankfurt am Main, Germany
| | | | - Tracy Lau
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
| | - David Murphy
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
| | - Niccolo Emanuele Mencacci
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Katharina Steindl
- Institute of Medical Genetics, University of Zurich, 8952 Schlieren, Switzerland
| | - Anais Begemann
- Institute of Medical Genetics, University of Zurich, 8952 Schlieren, Switzerland
| | - Anita Rauch
- Institute of Medical Genetics, University of Zurich, 8952 Schlieren, Switzerland
| | - Sinan Akbas
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, 34093 Istanbul, Turkey
| | - Ayça Dilruba Aslanger
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, 34093 Istanbul, Turkey
| | - Vincenzo Salpietro
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
- Department of Biotechnological and Applied Clinical Sciences (DISCAB), University of L’Aquila, 67100 L’Aquila, Italy
| | - Hammad Yousaf
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE) College, PIEAS, 44000 Faisalabad, Pakistan
| | - Shay Ben-Shachar
- Clalit Research Institute, Clalit Health Services, 6578898 Ramat Gan, Israel
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Katarina Ejeskär
- School of Health Science, Division Biomedicine and Translational Medicine, University of Skovde, SE-541 28 Skovde, Sweden
| | - Aida I Al Aqeel
- Department of Pediatrics, Prince Sultan Military Medical City, 12233 Riyadh, Saudi Arabia
- American University of Beirut, 1107 2020 Beirut, Lebanon
- Alfaisal University, 11533 Riyadh, Saudi Arabia
| | - Frances A High
- Division of Medical Genetics, Massachusetts General Hospital, Boston, MA 02114, USA
- Harvard Medical School, Boston, MA 02115, USA
| | - Amy E Armstrong-Javors
- Harvard Medical School, Boston, MA 02115, USA
- Department of Pediatric Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
| | | | - Tahereh Seifi
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Kianpars, Ahvaz, Iran
| | - Jawaher Zeighami
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Kianpars, Ahvaz, Iran
- Ati Mehr Kasra Genetics Institute, Kianpars, Ahvaz, Iran
| | - Gholamreza Shariati
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Kianpars, Ahvaz, Iran
- Department of Medical Genetics, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Alireza Sedaghat
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Kianpars, Ahvaz, Iran
- Diabetes Research center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Samaneh Noroozi Asl
- Department of Pediatrics Endocrinology, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohmmad Shahrooei
- Specialized Immunology Laboratory of Dr Shahrooei, Sina Medical Complex, Ahvaz, Iran
- Department of Microbiology and Immunology, Clinical and Diagnostic Immunology, KU Leuven, 3000 Leuven, Belgium
| | | | - Lydie Burglen
- Cerebellar Malformations and Congenital diseases Reference Center and Neurogenetics Lab, Department of Genetics, Armand Trousseau Hospital, AP-HP Sorbonne Université, 75006 Paris, France
- Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, 75015 Paris, France
| | - Claudia Ravelli
- Pediatric Neurology Department, Movement Disorders Center, Armand Trousseau Hospital, AP-HP Sorbonne Université, 75006 Paris, France
| | - Johannes Zschocke
- Institute of Human Genetics, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Ulrich A Schatz
- Institute of Human Genetics, Medical University Innsbruck, 6020 Innsbruck, Austria
- Institute of Human Genetics, Klinikum rechts der Isar, Technische Universität Munich, 81675 Munich, Germany
| | | | - Walaa A Kamel
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Department of Neurology, Faculty of Medicine, Beni-Suef University, 62521 Beni Suef, Egypt
| | - Hilde Van Esch
- Center for Human Genetics, University Hospitals Leuven, 3000 Leuven, Belgium
- Laboratory for the Genetics of Cognition, Department of Human Genetics, KU Leuven–University of Leuven, 3000 Leuven, Belgium
| | - Annette Hackenberg
- Department of Pediatric Neurology, University Children's Hospital Zürich, University of Zürich, 8032 Zürich, Switzerland
| | - Jenny C Taylor
- Wellcome Centre for Human Genetics, University of Oxford and Oxford NIHR Biomedical Research Centre, Oxford, OX3 7BN UK
| | - Lihadh Al-Gazali
- Departments of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, UAE
| | | | - Joseph J Gleeson
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
- Rady Children’s Institute for Genomic Medicine, San Diego, CA 92025, USA
| | - Fowzan Sami Alkuraya
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children’s Hospital, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hamid Galehdari
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran
- Ati Mehr Kasra Genetics Institute, Kianpars, Ahvaz, Iran
| | - Reza Azizimalamiri
- Department of Pediatric Neurology, Golestan Medical, Educational, and Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Wendy K Chung
- Boston Children’s Hospital and Harvard Medical School Boston, MA 02115, USA
| | - Shahid Mahmood Baig
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE) College, PIEAS, 44000 Faisalabad, Pakistan
- Department of Biological and Biomedical Sciences, Aga Khan University, 74800 Karachi, Pakistan
| | - Henry Houlden
- Department of Neuromuscular Diseases, University College London, Queen Square, Institute of Neurology, London WC1N 3BG, UK
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7
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Lin SJ, Vona B, Lau T, Huang K, Zaki MS, Aldeen HS, Karimiani EG, Rocca C, Noureldeen MM, Saad AK, Petree C, Bartolomaeus T, Abou Jamra R, Zifarelli G, Gotkhindikar A, Wentzensen IM, Liao M, Cork EE, Varshney P, Hashemi N, Mohammadi MH, Rad A, Neira J, Toosi MB, Knopp C, Kurth I, Challman TD, Smith R, Abdalla A, Haaf T, Suri M, Joshi M, Chung WK, Moreno-De-Luca A, Houlden H, Maroofian R, Varshney GK. Evaluating the association of biallelic OGDHL variants with significant phenotypic heterogeneity. Genome Med 2023; 15:102. [PMID: 38031187 PMCID: PMC10688095 DOI: 10.1186/s13073-023-01258-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 11/13/2023] [Indexed: 12/01/2023] Open
Abstract
BACKGROUND Biallelic variants in OGDHL, encoding part of the α-ketoglutarate dehydrogenase complex, have been associated with highly heterogeneous neurological and neurodevelopmental disorders. However, the validity of this association remains to be confirmed. A second OGDHL patient cohort was recruited to carefully assess the gene-disease relationship. METHODS Using an unbiased genotype-first approach, we screened large, multiethnic aggregated sequencing datasets worldwide for biallelic OGDHL variants. We used CRISPR/Cas9 to generate zebrafish knockouts of ogdhl, ogdh paralogs, and dhtkd1 to investigate functional relationships and impact during development. Functional complementation with patient variant transcripts was conducted to systematically assess protein functionality as a readout for pathogenicity. RESULTS A cohort of 14 individuals from 12 unrelated families exhibited highly variable clinical phenotypes, with the majority of them presenting at least one additional variant, potentially accounting for a blended phenotype and complicating phenotypic understanding. We also uncovered extreme clinical heterogeneity and high allele frequencies, occasionally incompatible with a fully penetrant recessive disorder. Human cDNA of previously described and new variants were tested in an ogdhl zebrafish knockout model, adding functional evidence for variant reclassification. We disclosed evidence of hypomorphic alleles as well as a loss-of-function variant without deleterious effects in zebrafish variant testing also showing discordant familial segregation, challenging the relationship of OGDHL as a conventional Mendelian gene. Going further, we uncovered evidence for a complex compensatory relationship among OGDH, OGDHL, and DHTKD1 isoenzymes that are associated with neurodevelopmental disorders and exhibit complex transcriptional compensation patterns with partial functional redundancy. CONCLUSIONS Based on the results of genetic, clinical, and functional studies, we formed three hypotheses in which to frame observations: biallelic OGDHL variants lead to a highly variable monogenic disorder, variants in OGDHL are following a complex pattern of inheritance, or they may not be causative at all. Our study further highlights the continuing challenges of assessing the validity of reported disease-gene associations and effects of variants identified in these genes. This is particularly more complicated in making genetic diagnoses based on identification of variants in genes presenting a highly heterogenous phenotype such as "OGDHL-related disorders".
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Affiliation(s)
- Sheng-Jia Lin
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Barbara Vona
- Institute of Human Genetics, Julius Maximilians University Würzburg, Würzburg, Germany
- Institute of Human Genetics, University Medical Center Göttingen, Göttingen, Germany
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, Göttingen, Germany
- Department of Otolaryngology-Head and Neck Surgery, Tübingen Hearing Research Center, Eberhard Karls University, Tübingen, 72076, Germany
| | - Tracy Lau
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Kevin Huang
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | - Huda Shujaa Aldeen
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Ehsan Ghayoor Karimiani
- Molecular and Clinical Sciences Institute, St. George's, University of London, Cranmer Terrace London, London, UK
| | - Clarissa Rocca
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Mahmoud M Noureldeen
- Department of Pediatrics, Faculty of Medicine, Beni-Suef University, Beni-Suef, Egypt
| | - Ahmed K Saad
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | - Cassidy Petree
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Tobias Bartolomaeus
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Rami Abou Jamra
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | | | | | | | | | - Emalyn Elise Cork
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Pratishtha Varshney
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Narges Hashemi
- Department of Pediatrics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Aboulfazl Rad
- Department of Otolaryngology-Head and Neck Surgery, Tübingen Hearing Research Center, Eberhard Karls University, Tübingen, 72076, Germany
| | - Juanita Neira
- Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA
| | - Mehran Beiraghi Toosi
- Department of Pediatrics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Cordula Knopp
- Institute for Human Genetics and Genomic Medicine, RWTH Aachen University, Pauwelsstr. 30, Aachen, 52074, Germany
| | - Ingo Kurth
- Institute for Human Genetics and Genomic Medicine, RWTH Aachen University, Pauwelsstr. 30, Aachen, 52074, Germany
| | - Thomas D Challman
- Autism & Developmental Medicine Institute, Geisinger, Lewisburg, PA, USA
| | - Rebecca Smith
- Autism & Developmental Medicine Institute, Geisinger, Lewisburg, PA, USA
| | - Asmahan Abdalla
- Department of Pediatric Endocrinology, Gaafar Ibn Auf Children's Tertiary Hospital, Khartoum, Sudan
| | - Thomas Haaf
- Institute of Human Genetics, Julius Maximilians University Würzburg, Würzburg, Germany
| | - Mohnish Suri
- Nottingham Clinical Genetics Service, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Manali Joshi
- Bioinformatics Centre, S. P. Pune University, Pune, India
| | - Wendy K Chung
- Department of Pediatrics, Boston Children's Hospitaland, Harvard Medical School , Boston, MA, USA
| | - Andres Moreno-De-Luca
- Department of Diagnostic Radiology, Kingston Health Sciences Centre, Queen's University, Kingston, ON, Canada
| | - Henry Houlden
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Reza Maroofian
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK.
| | - Gaurav K Varshney
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA.
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8
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Accogli A, Zaki MS, Al-Owain M, Otaif MY, Jackson A, Argilli E, Chandler KE, De Goede CGEL, Cora T, Alvi JR, Eslahi A, Asl Mohajeri MS, Ashtiani S, Au PYB, Scocchia A, Alakurtti K, Pagnamenta AT, Toosi MB, Karimiani EG, Mojarrad M, Arab F, Duymuş F, Scantlebury MH, Yeşil G, Rosenfeld JA, Türkyılmaz A, Sağer SG, Sultan T, Ashrafzadeh F, Zahra T, Rahman F, Maqbool S, Abdel-Hamid MS, Issa MY, Efthymiou S, Bauer P, Zifarelli G, Salpietro V, Al-Hassnan Z, Banka S, Sherr EH, Gleeson JG, Striano P, Houlden H, Severino M, Maroofian R. Lunapark deficiency leads to an autosomal recessive neurodevelopmental phenotype with a degenerative course, epilepsy and distinct brain anomalies. Brain Commun 2023; 5:fcad222. [PMID: 37794925 PMCID: PMC10546953 DOI: 10.1093/braincomms/fcad222] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 06/29/2023] [Accepted: 08/15/2023] [Indexed: 10/06/2023] Open
Abstract
LNPK encodes a conserved membrane protein that stabilizes the junctions of the tubular endoplasmic reticulum network playing crucial roles in diverse biological functions. Recently, homozygous variants in LNPK were shown to cause a neurodevelopmental disorder (OMIM#618090) in four patients displaying developmental delay, epilepsy and nonspecific brain malformations including corpus callosum hypoplasia and variable impairment of cerebellum. We sought to delineate the molecular and phenotypic spectrum of LNPK-related disorder. Exome or genome sequencing was carried out in 11 families. Thorough clinical and neuroradiological evaluation was performed for all the affected individuals, including review of previously reported patients. We identified 12 distinct homozygous loss-of-function variants in 16 individuals presenting with moderate to profound developmental delay, cognitive impairment, regression, refractory epilepsy and a recognizable neuroimaging pattern consisting of corpus callosum hypoplasia and signal alterations of the forceps minor ('ear-of-the-lynx' sign), variably associated with substantia nigra signal alterations, mild brain atrophy, short midbrain and cerebellar hypoplasia/atrophy. In summary, we define the core phenotype of LNPK-related disorder and expand the list of neurological disorders presenting with the 'ear-of-the-lynx' sign suggesting a possible common underlying mechanism related to endoplasmic reticulum-phagy dysfunction.
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Affiliation(s)
- Andrea Accogli
- Division of Medical Genetics, Department of Specialized Medicine, McGill University, Montreal H3G 1A4, Canada
- Department of Human Genetics, McGill University, Montreal, QC H3A 0C7, Canada
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo 12622, Egypt
| | - Mohammed Al-Owain
- Department of Medical Genomics, Center for Genomics Medicine, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - Mansour Y Otaif
- Department of Pediatric, Neurology Section, Abha Maternity and Childern Hospital, Abha 62521, Saudi Arabia
| | - Adam Jackson
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK
- Manchester Centre for Genomic Medicine, University of Manchester, St Mary’s Hospital, Manchester Academic Health Science Centre, Manchester M13 9WL, UK
| | - Emanuela Argilli
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Kate E Chandler
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK
- Manchester Centre for Genomic Medicine, University of Manchester, St Mary’s Hospital, Manchester Academic Health Science Centre, Manchester M13 9WL, UK
| | - Christian G E L De Goede
- Department of Paediatric Neurology, Clinical Research Facility, Lancashire Teaching Hospital NHS Trust, Preston PR2 9HT, UK
| | - Tülün Cora
- Department of Medical Genetics, Selcuk University School of Medicine, Konya 42100, Turkey
| | - Javeria Raza Alvi
- Department of Pediatric Neurology, Institute of Child Health, Children's Hospital, Lahore 54590, Pakistan
| | - Atieh Eslahi
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad 917794-8564, Iran
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad 9137-86177, Iran
| | - Mahsa Sadat Asl Mohajeri
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad 917794-8564, Iran
| | - Setareh Ashtiani
- Alberta Children’s Hospital Research Institute, Department of Medical Genetics, University of Calgary, Alberta T2N 4Z6, Canada
| | - P Y Billie Au
- Alberta Children’s Hospital Research Institute, Department of Medical Genetics, University of Calgary, Alberta T2N 4Z6, Canada
| | | | | | - Alistair T Pagnamenta
- NIHR Biomedical Research Centre, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Mehran Beiraghi Toosi
- Pediatric Neurology Department, Mashhad University of Medical Sciences, Mashhad 913791-6847, Iran
- Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad 91375-33116, Iran
| | - Ehsan Ghayoor Karimiani
- Molecular and Clinical Sciences Institute, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK
- Department of Medical Genetics, Next Generation Genetic Polyclinic, Mashhad 91869-51591, Iran
| | - Majid Mojarrad
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad 917794-8564, Iran
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad 9137-86177, Iran
- Genetic Center of Khorasan Razavi, Mashhad 91877-53831, Iran
| | - Fatemeh Arab
- Department of Medical Genetics, Faculty of Medicine, Tehran University of Medical Sciences, Tehran 1411713135, Iran
| | - Fahrettin Duymuş
- Department of Medical Genetics, Selcuk University School of Medicine, Konya 42100, Turkey
- Department of Medical Genetics, Konya City Hospital, Konya 42020, Turkey
| | - Morris H Scantlebury
- Departments of Pediatrics and Clinical Neuroscience, University of Calgary; Alberta Children’s Hospital Research Institute, Hotchkiss Brain Institute & Owerko Center, University of Calgary, Alberta T2N 4N1, Canada
| | - Gözde Yeşil
- Department of Medical Genetics, Istanbul Medical Faculty, Istanbul University, Istanbul 34093, Turkey
| | - Jill Anne Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Baylor Genetics Laboratories, Houston, TX 77021, USA
| | - Ayberk Türkyılmaz
- Department of Medical Genetics, Karadeniz Technical University Faculty of Medicine, Trabzon 61080, Turkey
| | - Safiye Güneş Sağer
- Clinics of Pediatric Neurology, Kartal Dr. Lütfi Kırdar City Hospital, İstanbul 34890, Turkey
| | - Tipu Sultan
- Department of Pediatric Neurology, Institute of Child Health, Children's Hospital, Lahore 54590, Pakistan
| | - Farah Ashrafzadeh
- Pediatric Neurology Department, Mashhad University of Medical Sciences, Mashhad 913791-6847, Iran
| | - Tatheer Zahra
- Department of Developmental-Behavioral Pediatrics, University of Child Health Sciences, The Children’s Hospital, Lahore 54590, Pakistan
| | - Fatima Rahman
- Department of Developmental-Behavioral Pediatrics, University of Child Health Sciences, The Children’s Hospital, Lahore 54590, Pakistan
| | - Shazia Maqbool
- Department of Developmental-Behavioral Pediatrics, University of Child Health Sciences, The Children’s Hospital, Lahore 54590, Pakistan
| | - Mohamed S Abdel-Hamid
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo 12622, Egypt
| | - Mahmoud Y Issa
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo 12622, Egypt
| | - Stephanie Efthymiou
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | | | | | - Vincenzo Salpietro
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila 67100, Italy
| | - Zuhair Al-Hassnan
- Department of Medical Genomics, Center for Genomics Medicine, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
- College of Medicine, Alfaisal University, Riyadh 11533, Saudi Arabia
| | - Siddharth Banka
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK
- Manchester Centre for Genomic Medicine, University of Manchester, St Mary’s Hospital, Manchester Academic Health Science Centre, Manchester M13 9WL, UK
| | - Elliot H Sherr
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Joseph G Gleeson
- Department of Neurosciences, University of California, San Diego, La Jolla 92093, USA
- Rady Children’s Institute for Genomic Medicine, San Diego 92123, USA
| | - Pasquale Striano
- Department of Neurosciences Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, Genoa 16132, Italy
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto ‘Giannina Gaslini’, Genoa 16147, Italy
| | - Henry Houlden
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | | | - Reza Maroofian
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
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9
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Saffari A, Lau T, Tajsharghi H, Karimiani EG, Kariminejad A, Efthymiou S, Zifarelli G, Sultan T, Toosi MB, Sedighzadeh S, Siu VM, Ortigoza-Escobar JD, AlShamsi AM, Ibrahim S, Al-Sannaa NA, Al-Hertani W, Sandra W, Tarnopolsky M, Alavi S, Li C, Day-Salvatore DL, Martínez-González MJ, Levandoski KM, Bedoukian E, Madan-Khetarpal S, Idleburg MJ, Menezes MJ, Siddharth A, Platzer K, Oppermann H, Smitka M, Collins F, Lek M, Shahrooei M, Ghavideldarestani M, Herman I, Rendu J, Faure J, Baker J, Bhambhani V, Calderwood L, Akhondian J, Imannezhad S, Mirzadeh HS, Hashemi N, Doosti M, Safi M, Ahangari N, Torbati PN, Abedini S, Salpietro V, Gulec EY, Eshaghian S, Ghazavi M, Pascher MT, Vogel M, Abicht A, Moutton S, Bruel AL, Rieubland C, Gallati S, Strom TM, Lochmüller H, Mohammadi MH, Alvi JR, Zackai EH, Keena BA, Skraban CM, Berger SI, Andrew EH, Rahimian E, Morrow MM, Wentzensen IM, Millan F, Henderson LB, Dafsari HS, Jungbluth H, Gomez-Ospina N, McRae A, Peter M, Veltra D, Marinakis NM, Sofocleous C, Ashrafzadeh F, Pehlivan D, Lemke JR, Melki J, Benezit A, Bauer P, Weis D, Lupski JR, Senderek J, Christodoulou J, Chung WK, Goodchild R, Offiah AC, Moreno-De-Luca A, Suri M, Ebrahimi-Fakhari D, Houlden H, Maroofian R. The clinical and genetic spectrum of autosomal-recessive TOR1A-related disorders. Brain 2023; 146:3273-3288. [PMID: 36757831 PMCID: PMC10393417 DOI: 10.1093/brain/awad039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 12/20/2022] [Accepted: 01/23/2023] [Indexed: 02/10/2023] Open
Abstract
In the field of rare diseases, progress in molecular diagnostics led to the recognition that variants linked to autosomal-dominant neurodegenerative diseases of later onset can, in the context of biallelic inheritance, cause devastating neurodevelopmental disorders and infantile or childhood-onset neurodegeneration. TOR1A-associated arthrogryposis multiplex congenita 5 (AMC5) is a rare neurodevelopmental disorder arising from biallelic variants in TOR1A, a gene that in the heterozygous state is associated with torsion dystonia-1 (DYT1 or DYT-TOR1A), an early-onset dystonia with reduced penetrance. While 15 individuals with AMC5-TOR1A have been reported (less than 10 in detail), a systematic investigation of the full disease-associated spectrum has not been conducted. Here, we assess the clinical, radiological and molecular characteristics of 57 individuals from 40 families with biallelic variants in TOR1A. Median age at last follow-up was 3 years (0-24 years). Most individuals presented with severe congenital flexion contractures (95%) and variable developmental delay (79%). Motor symptoms were reported in 79% and included lower limb spasticity and pyramidal signs, as well as gait disturbances. Facial dysmorphism was an integral part of the phenotype, with key features being a broad/full nasal tip, narrowing of the forehead and full cheeks. Analysis of disease-associated manifestations delineated a phenotypic spectrum ranging from normal cognition and mild gait disturbance to congenital arthrogryposis, global developmental delay, intellectual disability, absent speech and inability to walk. In a subset, the presentation was consistent with foetal akinesia deformation sequence with severe intrauterine abnormalities. Survival was 71%, with higher mortality in males. Death occurred at a median age of 1.2 months (1 week-9 years), due to respiratory failure, cardiac arrest or sepsis. Analysis of brain MRI studies identified non-specific neuroimaging features, including a hypoplastic corpus callosum (72%), foci of signal abnormality in the subcortical and periventricular white matter (55%), diffuse white matter volume loss (45%), mega cisterna magna (36%) and arachnoid cysts (27%). The molecular spectrum included 22 distinct variants, defining a mutational hotspot in the C-terminal domain of the Torsin-1A protein. Genotype-phenotype analysis revealed an association of missense variants in the 3-helix bundle domain to an attenuated phenotype, while missense variants near the Walker A/B motif as well as biallelic truncating variants were linked to early death. In summary, this systematic cross-sectional analysis of a large cohort of individuals with biallelic TOR1A variants across a wide age-range delineates the clinical and genetic spectrum of TOR1A-related autosomal-recessive disease and highlights potential predictors for disease severity and survival.
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Affiliation(s)
- Afshin Saffari
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Division of Child Neurology and Inherited Metabolic Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Tracy Lau
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, UK
| | - Homa Tajsharghi
- School of Health Sciences, Division of Biomedicine, University of Skovde, Skovde, Sweden
| | - Ehsan Ghayoor Karimiani
- Molecular and Clinical Sciences Institute, St. George's, University of London, Cranmer Terrace, London, UK
- Department of Medical Genetics, Next Generation Genetic Polyclinic, Mashhad, Iran
| | | | - Stephanie Efthymiou
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, UK
| | | | - Tipu Sultan
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, UK
| | - Mehran Beiraghi Toosi
- Department of Pediatrics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Sahar Sedighzadeh
- Department of Biological Sciences, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran
- KaryoGen, Isfahan, Iran
| | - Victoria Mok Siu
- Division of Medical Genetics, Department of Pediatrics, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Juan Darío Ortigoza-Escobar
- Movement Disorders Unit, Pediatric Neurology Department, Institut de Recerca, Hospital Sant Joan de Déu Barcelona, Barcelona, Spain
| | - Aisha M AlShamsi
- Genetic Division, Pediatrics Department, Tawam Hospital, Al Ain, UAE
| | - Shahnaz Ibrahim
- Department of pediatrics and child Health, Aga Khan University, Karachi, Pakistan
| | | | - Walla Al-Hertani
- Harvard Medical School, Boston Children's Hospital, Department of Pediatrics, Division of Genetics and Genomics, Boston, MA, USA
| | - Whalen Sandra
- APHP UF de Génétique Clinique, Centre de Référence des Anomalies du Développement et Syndromes Malformatifs, APHP, Hôpital Armand Trousseau, ERN ITHACA, Sorbonne Université, Paris, France
| | - Mark Tarnopolsky
- Department of Pediatrics (MT – Neuromuscular and Neurometabolics, CL – Medical Genetics), McMaster Children's Hospital, Hamilton, Ontario, Canada
| | - Shahryar Alavi
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, UK
| | - Chumei Li
- Department of Pediatrics (MT – Neuromuscular and Neurometabolics, CL – Medical Genetics), McMaster Children's Hospital, Hamilton, Ontario, Canada
| | - Debra-Lynn Day-Salvatore
- The Department of Medical Genetics and Genomic Medicine at Saint Peter's University Hospital, New Brunswick, NJ, USA
| | | | - Kristin M Levandoski
- The Department of Medical Genetics and Genomic Medicine at Saint Peter's University Hospital, New Brunswick, NJ, USA
| | - Emma Bedoukian
- Roberts Individualized Medical Genetics Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Suneeta Madan-Khetarpal
- Division of Genetic and Genomic Medicine, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Michaela J Idleburg
- Division of Genetic and Genomic Medicine, Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Minal Juliet Menezes
- Department of Anaesthesia, the Children's Hospital at Westmead, Sydney, NSW, Australia
- Discipline of Child and Adolescent Health, and Specialty of Genomic Medicine, Sydney Medical School, Sydney University, Sydney, NSW, Australia
| | - Aishwarya Siddharth
- Harvard Medical School, Boston Children's Hospital, Department of Pediatrics, Division of Genetics and Genomics, Boston, MA, USA
| | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Henry Oppermann
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Martin Smitka
- Department of Neuropediatrics, Medical Faculty Carl Gustav Carus, Technical University Dresden, Dresden, Germany
| | - Felicity Collins
- Discipline of Child and Adolescent Health, and Specialty of Genomic Medicine, Sydney Medical School, Sydney University, Sydney, NSW, Australia
- Department of Clinical Genetics, Children's Hospital at Westmead, Sydney, NSW, Australia
| | - Monkol Lek
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Mohmmad Shahrooei
- Medical Laboratory of Dr. Shahrooei, Tehran, Iran
- Department of Microbiology and Immunology, Clinical and Diagnostic Immunology, KU Leuven, Leuven, Belgium
| | | | - Isabella Herman
- Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Texas Children's Hospital, Houston, TX, USA
- Division of Pediatric Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
| | - John Rendu
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, Grenoble, France
| | - Julien Faure
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, Grenoble, France
| | - Janice Baker
- Division of Genetics and Genomic Medicine, Children's Hospital and Clinics of Minnesota, Minneapolis, Minnesota, USA
| | - Vikas Bhambhani
- Division of Genetics and Genomic Medicine, Children's Hospital and Clinics of Minnesota, Minneapolis, Minnesota, USA
| | - Laurel Calderwood
- Lucile Packard Children's Hospital Stanford, Palo Alto, CA, USA
- Department of Pediatrics, Division of Medical Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Javad Akhondian
- Pediatric Neurology Department, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Shima Imannezhad
- Department of Pediatric Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hanieh Sadat Mirzadeh
- Department of Pediatric Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Narges Hashemi
- Department of Pediatrics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad Doosti
- Department of Medical Genetics, Next Generation Genetic Polyclinic, Mashhad, Iran
| | - Mojtaba Safi
- Department of Medical Genetics, Next Generation Genetic Polyclinic, Mashhad, Iran
| | - Najmeh Ahangari
- Innovative medical research centre, Mashhad branch, Islamic Azad University, Mashhad, Iran
| | | | - Soheila Abedini
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, UK
| | - Vincenzo Salpietro
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, UK
| | - Elif Yilmaz Gulec
- Istanbul Medeniyet University Medical School, Department of Medical Genetics, Istanbul, Turkey
| | | | - Mohammadreza Ghazavi
- Department of Pediatric Neurology, Imam Hossein Children's Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Michael T Pascher
- Friedrich-Baur-Institute at the Department of Neurology, University Hospital, LMU Munich, Munich, Germany
| | - Marina Vogel
- Friedrich-Baur-Institute at the Department of Neurology, University Hospital, LMU Munich, Munich, Germany
- Deutsches Krebsforschungszentrum, Heidelberg, Germany
| | - Angela Abicht
- Friedrich-Baur-Institute at the Department of Neurology, University Hospital, LMU Munich, Munich, Germany
- Medizinisch Genetisches Zentrum, Munich, German
| | - Sébastien Moutton
- Multidisciplinary Center for Prenatal Diagnosis, Pôle Mère Enfant, Maison de Santé Protestante Bordeaux Bagatelle, Talence, France
| | - Ange-Line Bruel
- Équipe Génétique des Anomalies du Développement (GAD), INSERM UMR1231, Dijon, France
- Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, FHU-TRANSLAD, Dijon University Hospital, Dijon, France
| | - Claudine Rieubland
- Division of Human Genetics, Department of Pediatrics, Inselspital, University of Bern, Switzerland
| | - Sabina Gallati
- Division of Human Genetics, Department of Pediatrics, Inselspital, University of Bern, Switzerland
| | - Tim M Strom
- Institute of Human Genetics, Klinikum rechts der Isar, Technical University Munich, Munich, Germany
| | - Hanns Lochmüller
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Canada
- Division of Neurology, Department of Medicine, The Ottawa Hospital, Ottawa, Canada
| | | | - Javeria Raza Alvi
- Department of Pediatric Neurology, The Children's Hospital and the University of Child Health Sciences, Lahore, Pakistan
| | - Elaine H Zackai
- Division of Human Genetics, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Beth A Keena
- Division of Human Genetics, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Cara M Skraban
- Division of Human Genetics, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Seth I Berger
- Children's National Research Institute, Washington DC, USA
| | - Erin H Andrew
- Children's National Research Institute, Washington DC, USA
| | | | | | | | | | | | - Hormos Salimi Dafsari
- Department of Pediatrics, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Max-Planck-Institute for Biology of Ageing and CECAD, Cologne, Germany
- Department of Paediatric Neurology - Neuromuscular Service, Evelina London Children's Hospital, Guy's & St Thomas' Hospital NHS Foundation Trust, London, UK
| | - Heinz Jungbluth
- Department of Paediatric Neurology - Neuromuscular Service, Evelina London Children's Hospital, Guy's & St Thomas' Hospital NHS Foundation Trust, London, UK
- Randall Centre for Cell and Molecular Biophysics, Muscle Signalling Section, Faculty of Life Sciences and Medicine (FoLSM), King's College London, London, UK
| | | | - Anne McRae
- Division of Genetics, Genomics, and Metabolism, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, USA
| | - Merlene Peter
- Division of Genetics, Genomics, and Metabolism, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, USA
| | - Danai Veltra
- Laboratory of Medical Genetics, Medical School, National and Kapodistrian University of Athens, St. Sophia's Children's Hospital, Athens, Greece
| | - Nikolaos M Marinakis
- Laboratory of Medical Genetics, Medical School, National and Kapodistrian University of Athens, St. Sophia's Children's Hospital, Athens, Greece
| | - Christalena Sofocleous
- Laboratory of Medical Genetics, Medical School, National and Kapodistrian University of Athens, St. Sophia's Children's Hospital, Athens, Greece
| | - Farah Ashrafzadeh
- Department of Pediatric Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Davut Pehlivan
- Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Texas Children's Hospital, Houston, TX, USA
| | - Johannes R Lemke
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
- Center for Rare Diseases, University of Leipzig Medical Center, Leipzig, Germany
| | - Judith Melki
- Institut National de la Santé et de la Recherche Médicale (Inserm), UMR-1195, Université Paris Saclay, Le Kremlin Bicêtre, 94276, Paris, France
| | - Audrey Benezit
- Neurologie et réanimation pédiatrique, Hôpital Raymond Poincaré, APHP, Garches, France
| | - Peter Bauer
- CENTOGENE GmbH, Am Strande 7, 18055 Rostock, Germany
| | - Denisa Weis
- Department of Medical Genetics, Kepler University Hospital, Johann Kepler University, Linz, Austria
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Texas Children's Hospital, Houston, TX, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Jan Senderek
- Friedrich-Baur-Institute at the Department of Neurology, University Hospital, LMU Munich, Munich, Germany
| | - John Christodoulou
- Discipline of Child and Adolescent Health, and Specialty of Genomic Medicine, Sydney Medical School, Sydney University, Sydney, NSW, Australia
- Murdoch Children's Research Institute, Melbourne and Department of Paediatrics, Melbourne Medical School, University of Melbourne, Melbourne, VIC, Australia
| | - Wendy K Chung
- Department of Pediatrics and Medicine, Columbia University New York, NY, USA
| | - Rose Goodchild
- KU Leuven Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
- VIB-KU Leuven Center for Brain and Disease Research, Laboratory for Dystonia Research, Leuven, Belgium
| | - Amaka C Offiah
- Department of Oncology & Metabolism, University of Sheffield, UK
| | - Andres Moreno-De-Luca
- Autism & Developmental Medicine Institute, Genomic Medicine Institute, Department of Radiology, Diagnostic Medicine Institute, Geisinger, Danville, PA, USA
| | - Mohnish Suri
- Clinical Genetics Service, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Darius Ebrahimi-Fakhari
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Movement Disorders Program, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, USA
- Intellectual and Developmental Disabilities Research Center, Boston Children's Hospital, Boston, MA, USA
| | - Henry Houlden
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, UK
| | - Reza Maroofian
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, UK
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10
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Gracia-Diaz C, Zhou Y, Yang Q, Maroofian R, Espana-Bonilla P, Lee CH, Zhang S, Padilla N, Fueyo R, Waxman EA, Lei S, Otrimski G, Li D, Sheppard SE, Mark P, Harr MH, Hakonarson H, Rodan L, Jackson A, Vasudevan P, Powel C, Mohammed S, Maddirevula S, Alzaidan H, Faqeih EA, Efthymiou S, Turchetti V, Rahman F, Maqbool S, Salpietro V, Ibrahim SH, di Rosa G, Houlden H, Alharbi MN, Al-Sannaa NA, Bauer P, Zifarelli G, Estaras C, Hurst ACE, Thompson ML, Chassevent A, Smith-Hicks CL, de la Cruz X, Holtz AM, Elloumi HZ, Hajianpour MJ, Rieubland C, Braun D, Banka S, French DL, Heller EA, Saade M, Song H, Ming GL, Alkuraya FS, Agrawal PB, Reinberg D, Bhoj EJ, Martínez-Balbás MA, Akizu N. Gain and loss of function variants in EZH1 disrupt neurogenesis and cause dominant and recessive neurodevelopmental disorders. Nat Commun 2023; 14:4109. [PMID: 37433783 PMCID: PMC10336078 DOI: 10.1038/s41467-023-39645-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 06/22/2023] [Indexed: 07/13/2023] Open
Abstract
Genetic variants in chromatin regulators are frequently found in neurodevelopmental disorders, but their effect in disease etiology is rarely determined. Here, we uncover and functionally define pathogenic variants in the chromatin modifier EZH1 as the cause of dominant and recessive neurodevelopmental disorders in 19 individuals. EZH1 encodes one of the two alternative histone H3 lysine 27 methyltransferases of the PRC2 complex. Unlike the other PRC2 subunits, which are involved in cancers and developmental syndromes, the implication of EZH1 in human development and disease is largely unknown. Using cellular and biochemical studies, we demonstrate that recessive variants impair EZH1 expression causing loss of function effects, while dominant variants are missense mutations that affect evolutionarily conserved aminoacids, likely impacting EZH1 structure or function. Accordingly, we found increased methyltransferase activity leading to gain of function of two EZH1 missense variants. Furthermore, we show that EZH1 is necessary and sufficient for differentiation of neural progenitor cells in the developing chick embryo neural tube. Finally, using human pluripotent stem cell-derived neural cultures and forebrain organoids, we demonstrate that EZH1 variants perturb cortical neuron differentiation. Overall, our work reveals a critical role of EZH1 in neurogenesis regulation and provides molecular diagnosis for previously undefined neurodevelopmental disorders.
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Affiliation(s)
- Carolina Gracia-Diaz
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yijing Zhou
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Qian Yang
- Department of Neuroscience and Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, USA
| | - Reza Maroofian
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Paula Espana-Bonilla
- Department of Structural and Molecular Biology, Instituto de Biología Molecular de Barcelona (IBMB), Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
| | - Chul-Hwan Lee
- Department of Biomedical Sciences and Pharmacology, Seoul National University, College of Medicine, Seoul, South Korea
| | - Shuo Zhang
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, Philadelphia, PA, USA
| | - Natàlia Padilla
- Research Unit in Clinical and Translational Bioinformatics, Vall d'Hebron Institute of Research (VHIR), Universitat Autonoma de Barcelona, Barcelona, Spain
| | - Raquel Fueyo
- Department of Structural and Molecular Biology, Instituto de Biología Molecular de Barcelona (IBMB), Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
| | - Elisa A Waxman
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sunyimeng Lei
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Garrett Otrimski
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Dong Li
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sarah E Sheppard
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Paul Mark
- Department of Pediatrics, Division of Medical Genetics, Helen DeVos Children's Hospital, Corewell Health, Grand Rapids, MI, USA
| | - Margaret H Harr
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Hakon Hakonarson
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Lance Rodan
- Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Division of Genetics & Genomics, Boston Children's Hospital, Boston, MA, USA
| | - Adam Jackson
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, UK
| | - Pradeep Vasudevan
- Leicestershire Clinical Genetics Service, University Hospitals of Leicester NHS Trust, Leicester Royal Infirmary, Leicester, UK
| | - Corrina Powel
- Leicestershire Clinical Genetics Service, University Hospitals of Leicester NHS Trust, Leicester Royal Infirmary, Leicester, UK
| | | | - Sateesh Maddirevula
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Hamad Alzaidan
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Eissa A Faqeih
- Section of Medical Genetics, Children's Specialist Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Stephanie Efthymiou
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Valentina Turchetti
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Fatima Rahman
- Developmental and Behavioral Pediatrics, University of Child Health Sciences & The Children's Hospital, Lahore, Pakistan
| | - Shazia Maqbool
- Developmental and Behavioral Pediatrics, University of Child Health Sciences & The Children's Hospital, Lahore, Pakistan
| | - Vincenzo Salpietro
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Shahnaz H Ibrahim
- Department of Pediatrics and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Gabriella di Rosa
- Child Neuropsychiatry Unit, Department of Pediatrics, University of Messina, Messina, 98100, Italy
| | - Henry Houlden
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Maha Nasser Alharbi
- Maternity and Children Hospital Buraidah, Qassim Health Cluster, Buraydah, Saudi Arabia
| | | | | | | | - Conchi Estaras
- Center for Translational Medicine, Department of Cardiovascular Sciences, Temple University, Philadelphia, PA, USA
| | - Anna C E Hurst
- University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Anna Chassevent
- Department of Neurogenetics, Neurology and Developmental Medicine Kennedy Krieger Institute, Baltimore, MD, USA
| | - Constance L Smith-Hicks
- Department of Neurogenetics, Neurology and Developmental Medicine Kennedy Krieger Institute, Baltimore, MD, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Xavier de la Cruz
- Research Unit in Clinical and Translational Bioinformatics, Vall d'Hebron Institute of Research (VHIR), Universitat Autonoma de Barcelona, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Alexander M Holtz
- Division of Genetics & Genomics, Boston Children's Hospital, Boston, MA, USA
| | | | - M J Hajianpour
- Division of Medical Genetics and Genomics, Department of Pediatrics, Albany Medical College, Albany, NY, USA
| | - Claudine Rieubland
- Department of Human Genetics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Dominique Braun
- Department of Human Genetics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Siddharth Banka
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, UK
| | - Deborah L French
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Elizabeth A Heller
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, Philadelphia, PA, USA
| | - Murielle Saade
- Department of Structural and Molecular Biology, Instituto de Biología Molecular de Barcelona (IBMB), Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
| | - Hongjun Song
- Department of Neuroscience and Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, USA
| | - Guo-Li Ming
- Department of Neuroscience and Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, USA
| | - Fowzan S Alkuraya
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Pankaj B Agrawal
- Division of Genetics & Genomics, Boston Children's Hospital, Boston, MA, USA
- Division of Newborn Medicine, Boston Children's Hospital, Boston, MA, USA
- The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, USA
- Division of Neonatology, Department of Pediatrics, University of Miami School of Medicine and Holtz Children's Hospital, Jackson Heath System, Miami, FL, USA
| | | | - Elizabeth J Bhoj
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Marian A Martínez-Balbás
- Department of Structural and Molecular Biology, Instituto de Biología Molecular de Barcelona (IBMB), Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
| | - Naiara Akizu
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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11
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Engal E, Oja KT, Maroofian R, Geminder O, Le TL, Mor E, Tzvi N, Elefant N, Zaki MS, Gleeson JG, Muru K, Pajusalu S, Wojcik MH, Pachat D, Elmaksoud MA, Jeong WC, Lee H, Bauer P, Zifarelli G, Houlden H, Elpeleg O, Gordon C, Harel T, Õunap K, Salton M, Mor-Shaked H. Biallelic loss of function variants in WBP4, encoding a spliceosome protein, result in a variable neurodevelopmental delay syndrome. medRxiv 2023:2023.06.19.23291425. [PMID: 37425688 PMCID: PMC10327195 DOI: 10.1101/2023.06.19.23291425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Over two dozen spliceosome proteins are involved in human diseases, also referred to as spliceosomopathies. WBP4 (WW Domain Binding Protein 4) is part of the early spliceosomal complex, and was not described before in the context of human pathologies. Ascertained through GeneMatcher we identified eleven patients from eight families, with a severe neurodevelopmental syndrome with variable manifestations. Clinical manifestations included hypotonia, global developmental delay, severe intellectual disability, brain abnormalities, musculoskeletal and gastrointestinal abnormalities. Genetic analysis revealed overall five different homozygous loss-of-function variants in WBP4. Immunoblotting on fibroblasts from two affected individuals with different genetic variants demonstrated complete loss of protein, and RNA sequencing analysis uncovered shared abnormal splicing patterns, including enrichment for abnormalities of the nervous system and musculoskeletal system genes, suggesting that the overlapping differentially spliced genes are related to the common phenotypes of the probands. We conclude that biallelic variants in WBP4 cause a spliceosomopathy. Further functional studies are called for better understanding of the mechanism of pathogenicity.
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Affiliation(s)
- Eden Engal
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
- Department of Military Medicine and “Tzameret”, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Kaisa Teele Oja
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
- Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Reza Maroofian
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Ophir Geminder
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
- Department of Military Medicine and “Tzameret”, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | | | - Evyatar Mor
- Department of computer science, Ben-Gurion University of the Negev
| | - Naama Tzvi
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel
| | - Naama Elefant
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel
| | - Maha S. Zaki
- Department of Clinical Genetics, Human Genetics and Genome Research Institute, Cairo, Egypt
| | - Joseph G. Gleeson
- Department of Neurosciences, University of California, San Diego, La Jolla, USA
- Rady Children’s Institute for Genomic Medicine, San Diego, La Jolla, USA
| | - Kai Muru
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
- Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Sander Pajusalu
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
- Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | | | | | - Marwa Abd Elmaksoud
- Neurology Unit, Alexandria University Children’s Hospital, Department of Pediatrics, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | | | | | - Peter Bauer
- CENTOGENE N.V., Am Strande 7, 18055 Rostock, Germany
| | | | - Henry Houlden
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Orly Elpeleg
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel
- Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | | | - Tamar Harel
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel
- Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Katrin Õunap
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
- Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Maayan Salton
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Hagar Mor-Shaked
- Department of Genetics, Hadassah Medical Organization, Jerusalem, Israel
- Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
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12
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Koopmann TT, Jamshidi Y, Naghibi-Sistani M, van der Klift HM, Birjandi H, Al-Hassnan Z, Alwadai A, Zifarelli G, Karimiani EG, Sedighzadeh S, Bahreini A, Nouri N, Peter M, Watanabe K, van Duyvenvoorde HA, Ruivenkamp CAL, Teunissen AKK, Ten Harkel ADJ, van Duinen SG, Haak MC, Prada CE, Santen GWE, Maroofian R. Biallelic loss of LDB3 leads to a lethal pediatric dilated cardiomyopathy. Eur J Hum Genet 2023; 31:97-104. [PMID: 36253531 PMCID: PMC9823012 DOI: 10.1038/s41431-022-01204-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 09/20/2022] [Accepted: 09/23/2022] [Indexed: 02/08/2023] Open
Abstract
Autosomal dominant variants in LDB3 (also known as ZASP), encoding the PDZ-LIM domain-binding factor, have been linked to a late onset phenotype of cardiomyopathy and myofibrillar myopathy in humans. However, despite knockout mice displaying a much more severe phenotype with premature death, bi-allelic variants in LDB3 have not yet been reported. Here we identify biallelic loss-of-function variants in five unrelated cardiomyopathy families by next-generation sequencing. In the first family, we identified compound heterozygous LOF variants in LDB3 in a fetus with bilateral talipes and mild left cardiac ventricular enlargement. Ultra-structural examination revealed highly irregular Z-disc formation, and RNA analysis demonstrated little/no expression of LDB3 protein with a functional C-terminal LIM domain in muscle tissue from the affected fetus. In a second family, a homozygous LDB3 nonsense variant was identified in a young girl with severe early-onset dilated cardiomyopathy with left ventricular non-compaction; the same homozygous nonsense variant was identified in a third unrelated female infant with dilated cardiomyopathy. We further identified homozygous LDB3 frameshift variants in two unrelated probands diagnosed with cardiomegaly and severely reduced left ventricular ejection fraction. Our findings demonstrate that recessive LDB3 variants can lead to an early-onset severe human phenotype of cardiomyopathy and myopathy, reminiscent of the knockout mouse phenotype, and supporting a loss of function mechanism.
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Affiliation(s)
- Tamara T. Koopmann
- grid.10419.3d0000000089452978Department of Clinical Genetics/LDGA, Leiden University Medical Center, Leiden, The Netherlands
| | - Yalda Jamshidi
- grid.264200.20000 0000 8546 682XGenetics Research Centre, Molecular and Clinical Sciences Institute, St George’s University of London, London, UK
| | - Mohammad Naghibi-Sistani
- grid.411583.a0000 0001 2198 6209Pediatric & Congenital Cardiology Division, Pediatric Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Heleen M. van der Klift
- grid.10419.3d0000000089452978Department of Clinical Genetics/LDGA, Leiden University Medical Center, Leiden, The Netherlands
| | - Hassan Birjandi
- grid.411583.a0000 0001 2198 6209Pediatric & Congenital Cardiology Division, Pediatric Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Zuhair Al-Hassnan
- grid.415310.20000 0001 2191 4301The Cardiovascular Genetics Program, Centre for Genomic Medicine, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Abdullah Alwadai
- grid.415989.80000 0000 9759 8141PICU Department, Prince Sultan Cardiac Center, Riyadh, Saudi Arabia
| | - Giovanni Zifarelli
- grid.511058.80000 0004 0548 4972CENTOGENE GmbH, Am Strande 7, 18055 Rostock, Germany
| | - Ehsan G. Karimiani
- grid.264200.20000 0000 8546 682XGenetics Research Centre, Molecular and Clinical Sciences Institute, St George’s University of London, London, UK ,Department of Medical Genetics, Next Generation Genetic Polyclinic, Mashhad, Iran
| | - Sahar Sedighzadeh
- grid.412504.60000 0004 0612 5699Department of Biological Sciences, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran ,KaryoGen, Isfahan, Iran
| | - Amir Bahreini
- KaryoGen, Isfahan, Iran ,grid.21925.3d0000 0004 1936 9000Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA USA
| | - Nayereh Nouri
- KaryoGen, Isfahan, Iran ,grid.411036.10000 0001 1498 685XDepartment of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Merlene Peter
- grid.413808.60000 0004 0388 2248Division of Genetics, Birth Defects & Metabolism, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL 60611 USA
| | - Kyoko Watanabe
- grid.413808.60000 0004 0388 2248Division of Cardiology, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL 60611 USA
| | - Hermine A. van Duyvenvoorde
- grid.10419.3d0000000089452978Department of Clinical Genetics/LDGA, Leiden University Medical Center, Leiden, The Netherlands
| | - Claudia A. L. Ruivenkamp
- grid.10419.3d0000000089452978Department of Clinical Genetics/LDGA, Leiden University Medical Center, Leiden, The Netherlands
| | - Aalbertine K. K. Teunissen
- grid.10419.3d0000000089452978Department of Obstetrics and Prenatal Diagnosis, Leiden University Medical Center, Leiden, The Netherlands
| | - Arend D. J. Ten Harkel
- grid.10419.3d0000000089452978Department of Pediatric Cardiology, Willem Alexander Children’s Hospital, Leiden University Medical Center, Leiden, The Netherlands
| | - Sjoerd G. van Duinen
- grid.10419.3d0000000089452978Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - Monique C. Haak
- grid.10419.3d0000000089452978Department of Pediatric Cardiology, Willem Alexander Children’s Hospital, Leiden University Medical Center, Leiden, The Netherlands
| | - Carlos E. Prada
- grid.413808.60000 0004 0388 2248Division of Genetics, Birth Defects & Metabolism, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL 60611 USA ,grid.16753.360000 0001 2299 3507Department of Pediatrics, Feinberg School of Medicine of Northwestern University, Chicago, IL 60611 USA
| | - Gijs W. E. Santen
- grid.10419.3d0000000089452978Department of Clinical Genetics/LDGA, Leiden University Medical Center, Leiden, The Netherlands
| | - Reza Maroofian
- grid.83440.3b0000000121901201Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
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13
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Calì E, Lin SJ, Rocca C, Sahin Y, Al Shamsi A, El Chehadeh S, Chaabouni M, Mankad K, Galanaki E, Efthymiou S, Sudhakar S, Athanasiou-Fragkouli A, Çelik T, Narlı N, Bianca S, Murphy D, De Carvalho Moreira FM, Andrea Accogli, Petree C, Huang K, Monastiri K, Edizadeh M, Nardello R, Ognibene M, De Marco P, Ruggieri M, Zara F, Striano P, Şahin Y, Al-Gazali L, Abi Warde MT, Gerard B, Zifarelli G, Beetz C, Fortuna S, Soler M, Valente EM, Varshney G, Maroofian R, Salpietro V, Houlden H. A homozygous MED11 C-terminal variant causes a lethal neurodegenerative disease. Genet Med 2022; 24:2194-2203. [PMID: 36001086 PMCID: PMC10519206 DOI: 10.1016/j.gim.2022.07.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/07/2022] [Accepted: 07/11/2022] [Indexed: 02/05/2023] Open
Abstract
PURPOSE The mediator (MED) multisubunit-complex modulates the activity of the transcriptional machinery, and genetic defects in different MED subunits (17, 20, 27) have been implicated in neurologic diseases. In this study, we identified a recurrent homozygous variant in MED11 (c.325C>T; p.Arg109Ter) in 7 affected individuals from 5 unrelated families. METHODS To investigate the genetic cause of the disease, exome or genome sequencing were performed in 5 unrelated families identified via different research networks and Matchmaker Exchange. Deep clinical and brain imaging evaluations were performed by clinical pediatric neurologists and neuroradiologists. The functional effect of the candidate variant on both MED11 RNA and protein was assessed using reverse transcriptase polymerase chain reaction and western blotting using fibroblast cell lines derived from 1 affected individual and controls and through computational approaches. Knockouts in zebrafish were generated using clustered regularly interspaced short palindromic repeats/Cas9. RESULTS The disease was characterized by microcephaly, profound neurodevelopmental impairment, exaggerated startle response, myoclonic seizures, progressive widespread neurodegeneration, and premature death. Functional studies on patient-derived fibroblasts did not show a loss of protein function but rather disruption of the C-terminal of MED11, likely impairing binding to other MED subunits. A zebrafish knockout model recapitulates key clinical phenotypes. CONCLUSION Loss of the C-terminal of MED subunit 11 may affect its binding efficiency to other MED subunits, thus implicating the MED-complex stability in brain development and neurodegeneration.
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Affiliation(s)
- Elisa Calì
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Sheng-Jia Lin
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | - Clarissa Rocca
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Yavuz Sahin
- Department of Medical Genetics, Genoks Genetic Laboratory, Ankara, Turkey
| | | | - Salima El Chehadeh
- Service de Génétique Médicale, Institut de Génétique Médicale d'Alsace (IGMA), Centre de Référence des Déficiences Intellectuelles de Causes Rares, Centre de Recherche en Biomédecine de Strasbourg (CRBS), Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | | | - Kshitij Mankad
- Department of Radiology, Great Ormond Street Hospital for Children, London, United Kingdom
| | - Evangelia Galanaki
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Stephanie Efthymiou
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Sniya Sudhakar
- Department of Radiology, Great Ormond Street Hospital for Children, London, United Kingdom
| | | | - Tamer Çelik
- Department of Pediatric Neurology, Private Practice, Adana, Turkey
| | - Nejat Narlı
- Division of Neonatology, Department of Pediatrics, Medical School, Cukurova University, Adana, Turkey
| | - Sebastiano Bianca
- Medical Genetics, Referral Centre for Rare Genetic Diseases, ARNAS Garibaldi, Catania, Italy
| | - David Murphy
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
| | | | - Andrea Accogli
- Division of Medical Genetics, Department of Specialized Medicine, Montreal Children's Hospital, McGill University Health Centre (MUHC), Montreal, Quebec, Canada; Department of Human Genetics, McGill University, Montreal, Quebec, Canada
| | - Cassidy Petree
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | - Kevin Huang
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | - Kamel Monastiri
- Department of Neonatology, Fattouma Bourguiba Hospital, Monastir, Tunisia
| | - Masoud Edizadeh
- Department of Medical Genetics, Genoks Genetic Laboratory, Ankara, Turkey
| | - Rosaria Nardello
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
| | - Marzia Ognibene
- Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Patrizia De Marco
- Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Martino Ruggieri
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, AOU "Policlinico," University of Catania, Catania, Italy
| | - Federico Zara
- Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, Genoa, Italy; Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Pediatric Neurology and Muscular Diseases Unit, IRCCS "Istituto Giannina Gaslini," Genova, Italy
| | - Yavuz Şahin
- Department of Medical Genetics, Biruni University, İstanbul, Turkey
| | - Lihadh Al-Gazali
- Department of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | | | - Benedicte Gerard
- Laboratoires de Diagnostic Génétique, Unité de Génétique Moléculaire, Nouvel Hôpital Civil, Strasbourg Cedex, France
| | | | | | - Sara Fortuna
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Miguel Soler
- CONCEPT Lab, Italian Institute of Technology (IIT), Genova, Italy
| | - Enza Maria Valente
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Neurogenetics Research Center, IRCCS Mondino Foundation, Pavia, Italy
| | - Gaurav Varshney
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | - Reza Maroofian
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Vincenzo Salpietro
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom; Department of Pediatrics, University of L'Aquila, L'Aquila, Italy.
| | - Henry Houlden
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
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14
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Zifarelli G, Pusch M, Fong P. Altered voltage-dependence of slowly activating chloride-proton antiport by late endosomal ClC-6 explains distinct neurological disorders. J Physiol 2022; 600:2147-2164. [PMID: 35262198 DOI: 10.1113/jp282737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/01/2022] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Ionic composition and pH within intracellular compartments, such as endo-lysosomes, rely on the activity of chloride/proton transporters including ClC-6. Distinct CLCN6 mutations previously were found in individuals with neurodegenerative disease, and also putatively associated with neuronal ceroidal lipofuscinosis. Limited knowledge of wild-type ClC-6 transport function impedes understanding of mechanisms underlying these conditions. We resolved transient and transport currents that permit measurement of voltage- and pH- dependences, as well as kinetics, for wild-type and disease-associated mutant ClC-6s. These findings define wild-type ClC-6 function robustly, and reveal how alterations of the slow activation gating of the transporter cause different kinds of neurological diseases. ABSTRACT ClC-6 is an intracellularly localized member of the CLC family of chloride transport proteins. It presumably functions in the endo-lysosomal compartment as a chloride-proton antiporter, despite a paucity of biophysical studies in direct support. Observations of lysosomal storage disease, as well as neurodegenerative disorders, emerge with its disruption by knockout or mutation, respectively. An incomplete understanding of wild type ClC-6 function obscures clear mechanistic insight into disease etiology. Here, high-resolution recording protocols that incorporate extreme voltage pulses permit detailed biophysical measurement and analysis of transient capacitive, as well as ionic transport currents. This approach reveals that wild type ClC-6 activation and transport require depolarization to voltages beyond 140 mV. Mutant Y553C associated with early-onset neurodegeneration exerts gain-of-function by shifting the half-maximal voltage for activation to less depolarized voltages. Moreover, we show that the E267A proton glutamate mutant conserves transport currents, albeit reduced. Lastly, the positive shift in activation voltage shown by V580M, a mutant identified in a patient with late- onset lysosomal storage disease, can explain loss-of-function leading to disease. Abstract figure legend CLC transport proteins comprise both channels and transporters. Vesicular CLC transporters function to regulate compartmental ionic homeostasis and acidification. ClC-6 is a vesicular CLC that localizes to the endo-lysosomal compartment. Functional plasma membrane overexpression of GFP-tagged ClC-6 in HEK293 cells surmounted spatial inaccessibility, and rapid whole cell patch recording protocols enabling resolution of fast capacitive transients, as well as ionic transport currents, provided details of wild-type ClC-6 biophysical properties including voltage-dependence, pH-dependence, and kinetics. Clearly defined wild-type ClC-6 function permitted subsequent comparative analysis of mutants, including but not limited to those pertinent to disease. These range from one causing severe, early-onset neurodegeneration, to two variants previously identified in Kufs disease, a late-onset lysosomal storage disease characterized by neuronal ceroid lipofuscinosis. These findings further inform models whereby disruption of ClC-6 biophysical properties set the stage for dysregulated compartmental homeostasis and hence, disease. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Giovanni Zifarelli
- Institute of Biophysics, CNR, Genoa, Italy.,Present address: Centogene GmbH, Rostock, Germany
| | | | - Peying Fong
- Department of Anatomy and Physiology, Kansas State University College of Veterinary Medicine, Manhattan, KS, USA
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15
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Rössler U, Hennig AF, Stelzer N, Bose S, Kopp J, Søe K, Cyganek L, Zifarelli G, Ali S, von der Hagen M, Strässler ET, Hahn G, Pusch M, Stauber T, Izsvák Z, Gossen M, Stachelscheid H, Kornak U. Efficient generation of osteoclasts from human induced pluripotent stem cells and functional investigations of lethal CLCN7-related osteopetrosis. J Bone Miner Res 2021; 36:1621-1635. [PMID: 33905594 DOI: 10.1002/jbmr.4322] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 03/26/2021] [Accepted: 04/21/2021] [Indexed: 12/18/2022]
Abstract
Human induced pluripotent stem cells (hiPSCs) hold great potential for modeling human diseases and the development of innovative therapeutic approaches. Here, we report on a novel, simplified differentiation method for forming functional osteoclasts from hiPSCs. The three-step protocol starts with embryoid body formation, followed by hematopoietic specification, and finally osteoclast differentiation. We observed continuous production of monocyte-like cells over a period of up to 9 weeks, generating sufficient material for several osteoclast differentiations. The analysis of stage-specific gene and surface marker expression proved mesodermal priming, the presence of monocyte-like cells, and of terminally differentiated multinucleated osteoclasts, able to form resorption pits and trenches on bone and dentine in vitro. In comparison to peripheral blood mononuclear cell (PBMC)-derived osteoclasts hiPSC-derived osteoclasts were larger and contained a higher number of nuclei. Detailed functional studies on the resorption behavior of hiPSC-osteoclasts indicated a trend towards forming more trenches than pits and an increase in pseudoresorption. We used hiPSCs from an autosomal recessive osteopetrosis (ARO) patient (BIHi002-A, ARO hiPSCs) with compound heterozygous missense mutations p.(G292E) and p.(R403Q) in CLCN7, coding for the Cl- /H+ -exchanger ClC-7, for functional investigations. The patient's leading clinical feature was a brain malformation due to defective neuronal migration. Mutant ClC-7 displayed residual expression and retained lysosomal co-localization with OSTM1, the gene coding for the osteopetrosis-associated transmembrane protein 1, but only ClC-7 harboring the mutation p.(R403Q) gave strongly reduced ion currents. An increased autophagic flux in spite of unchanged lysosomal pH was evident in undifferentiated ARO hiPSCs. ARO hiPSC-derived osteoclasts showed an increased size compared to hiPSCs of healthy donors. They were not able to resorb bone, underlining a loss-of-function effect of the mutations. In summary, we developed a highly reproducible, straightforward hiPSC-osteoclast differentiation protocol. We demonstrated that osteoclasts differentiated from ARO hiPSCs can be used as a disease model for ARO and potentially also other osteoclast-related diseases. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Uta Rössler
- BIH Center for Regenerative Therapies (BCRT), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Berlin Institute of Health (BIH), Berlin, Germany
| | - Anna Floriane Hennig
- BIH Center for Regenerative Therapies (BCRT), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Freie Universität Berlin, Berlin, Germany.,Institute of Human Genetics, University Medical Center Göttingen, Göttingen, Germany
| | - Nina Stelzer
- BIH Center for Regenerative Therapies (BCRT), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Shroddha Bose
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Johannes Kopp
- BIH Center for Regenerative Therapies (BCRT), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Freie Universität Berlin, Berlin, Germany.,Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Kent Søe
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, Odense C, Denmark.,Department of Clinical Research, University of Southern Denmark, Odense M, Denmark.,Department of Molecular Medicine, University of Southern Denmark, Odense M, Denmark
| | - Lukas Cyganek
- Stem Cell Unit, Clinic for Cardiology and Pneumology, University Medical Center Göttingen, Göttingen, Germany.,German Center for Cardiovascular Research (DZHK), Partner Site Göttingen, Göttingen, Germany
| | | | - Salaheddine Ali
- BIH Center for Regenerative Therapies (BCRT), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Maja von der Hagen
- Abteilung Neuropädiatrie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Elisabeth Tamara Strässler
- Department of Cardiology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany.,German Centre for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany
| | - Gabriele Hahn
- Institut und Poliklinik für Radiologische Diagnostik, Medizinische Fakultät Carl Gustav Carus Technische Universität Dresden, Dresden, Germany
| | | | - Tobias Stauber
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany.,Department of Human Medicine, and Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Zsuzsanna Izsvák
- Max-Delbrück-Center for Molecular Medicine (MDC), Helmholtz Association, Berlin, Germany
| | - Manfred Gossen
- Berlin-Brandenburg Center for Regenerative Therapies, Charité Virchow Campus, Berlin, Germany.,Institute of Active Polymers, Helmholtz-Zentrum Hereon, Teltow, Germany
| | - Harald Stachelscheid
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Berlin Institute of Health (BIH), BIH Stem Cell Core Facility, Berlin, Germany
| | - Uwe Kornak
- BIH Center for Regenerative Therapies (BCRT), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Institute of Human Genetics, University Medical Center Göttingen, Göttingen, Germany.,Max Planck Institute for Molecular Genetics, Berlin, Germany
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16
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Remigante A, Morabito R, Marino A, Scimemi P, Picco C, Santarelli R, Zifarelli G, Dossena S, Pusch M. Reduction of Kir4.1 channel activity in an oxidative stress‐related aging model. FASEB J 2021. [DOI: 10.1096/fasebj.2021.35.s1.01854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Alessia Remigante
- Department of Chemical, Biological, Pharmaceutical and Environmental SciencesUniversity of MessinaMessina
| | - Rossana Morabito
- Department of Chemical, Biological, Pharmaceutical and Environmental SciencesUniversity of MessinaMessina
| | - Angela Marino
- Department of Chemical, Biological, Pharmaceutical and Environmental SciencesUniversity of MessinaMessina
| | - Pietro Scimemi
- Department of Neuroscience‐DNS19 / 5000 Risultati della traduzione School of MedicineUniversity of PaduaPadua
| | | | | | | | - Silvia Dossena
- Institute of Pharmacology and ToxicologyParacelsus Medizinische PrivatuniversitätSalzburg
| | - Michael Pusch
- Biophysics InstituteNational Council of ResearchGenoa
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17
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Pusch M, Zifarelli G. Large transient capacitive currents in wild-type lysosomal Cl-/H+ antiporter ClC-7 and residual transport activity in the proton glutamate mutant E312A. J Gen Physiol 2020; 153:211547. [PMID: 33211806 PMCID: PMC7681918 DOI: 10.1085/jgp.202012583] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 09/28/2020] [Accepted: 10/28/2020] [Indexed: 12/18/2022] Open
Abstract
ClC-7 is a lysosomal 2 Cl−/1 H+ antiporter of the CLC protein family, which comprises Cl− channels and other Cl−/H+ antiporters. Mutations in ClC-7 and its associated β subunit Ostm1 lead to osteopetrosis and lysosomal storage disease in humans and mice. Previous studies on other mammalian CLC transporters showed that mutations of a conserved, intracellularly located glutamate residue, the so-called proton glutamate, abolish steady-state transport activity but increase transient capacitive currents associated with partial reactions of the transport cycle. In contrast, we observed large, transient capacitive currents for the wild-type ClC-7, which depend on external pH and internal, but not external, Cl−. Very similar transient currents were observed for the E312A mutant of the proton glutamate. Interestingly, and unlike in other mammalian CLC transporters investigated so far, the E312A mutation strongly reduces, but does not abolish, stationary transport currents, potentially explaining the intermediate phenotype observed in the E312A mouse line.
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Affiliation(s)
- Michael Pusch
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Genoa, Italy
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18
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Lagostena L, Zifarelli G, Picollo A. New Insights into the Mechanism of NO 3 - Selectivity in the Human Kidney Chloride Channel ClC-Ka and the CLC Protein Family. J Am Soc Nephrol 2019; 30:293-302. [PMID: 30635372 DOI: 10.1681/asn.2018060593] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 12/01/2018] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND The mechanism of anion selectivity in the human kidney chloride channels ClC-Ka and ClC-Kb is unknown. However, it has been thought to be very similar to that of other channels and antiporters of the CLC protein family, and to rely on anions interacting with a conserved Ser residue (Sercen) at the center of three anion binding sites in the permeation pathway Scen. In both CLC channels and antiporters, mutations of Sercen alter the anion selectivity. Structurally, the side chain of Sercen of CLC channels and antiporters typically projects into the pore and coordinates the anion bound at Scen. METHODS To investigate the role of several residues in anion selectivity of ClC-Ka, we created mutations that resulted in amino acid substitutions in these residues. We also used electrophysiologic techniques to assess the properties of the mutants. RESULTS Mutations in ClC-Ka that change Sercen to Gly, Pro, or Thr have only minor effects on anion selectivity, whereas the mutations in residues Y425A, F519A, and Y520A increase the NO3 -/Cl- permeability ratio, with Y425A having a particularly strong effect. CONCLUSION s ClC-Ka's mechanism of anion selectivity is largely independent of Sercen, and it is therefore unique in the CLC protein family. We identified the residue Y425 in ClC-Ka-and the corresponding residue (A417) in the chloride channel ClC-0-as residues that contribute to NO3 - discrimination in these channels. This work provides important and timely insight into the relationship between structure and function for the kidney chloride channels ClC-Ka and ClC-Kb, and for CLC proteins in general.
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Affiliation(s)
- Laura Lagostena
- Dulbecco Telethon Laboratory, Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Genova, Italy; and
| | - Giovanni Zifarelli
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Alessandra Picollo
- Dulbecco Telethon Laboratory, Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Genova, Italy; and
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19
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Ando T, Bhamidimarri SP, Brending N, Colin-York H, Collinson L, De Jonge N, de Pablo PJ, Debroye E, Eggeling C, Franck C, Fritzsche M, Gerritsen H, Giepmans BNG, Grunewald K, Hofkens J, Hoogenboom JP, Janssen KPF, Kaufman R, Klumpermann J, Kurniawan N, Kusch J, Liv N, Parekh V, Peckys DB, Rehfeldt F, Reutens DC, Roeffaers MBJ, Salditt T, Schaap IAT, Schwarz US, Verkade P, Vogel MW, Wagner R, Winterhalter M, Yuan H, Zifarelli G. The 2018 correlative microscopy techniques roadmap. J Phys D Appl Phys 2018; 51:443001. [PMID: 30799880 PMCID: PMC6372154 DOI: 10.1088/1361-6463/aad055] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 06/14/2018] [Accepted: 07/01/2018] [Indexed: 05/19/2023]
Abstract
Developments in microscopy have been instrumental to progress in the life sciences, and many new techniques have been introduced and led to new discoveries throughout the last century. A wide and diverse range of methodologies is now available, including electron microscopy, atomic force microscopy, magnetic resonance imaging, small-angle x-ray scattering and multiple super-resolution fluorescence techniques, and each of these methods provides valuable read-outs to meet the demands set by the samples under study. Yet, the investigation of cell development requires a multi-parametric approach to address both the structure and spatio-temporal organization of organelles, and also the transduction of chemical signals and forces involved in cell-cell interactions. Although the microscopy technologies for observing each of these characteristics are well developed, none of them can offer read-out of all characteristics simultaneously, which limits the information content of a measurement. For example, while electron microscopy is able to disclose the structural layout of cells and the macromolecular arrangement of proteins, it cannot directly follow dynamics in living cells. The latter can be achieved with fluorescence microscopy which, however, requires labelling and lacks spatial resolution. A remedy is to combine and correlate different readouts from the same specimen, which opens new avenues to understand structure-function relations in biomedical research. At the same time, such correlative approaches pose new challenges concerning sample preparation, instrument stability, region of interest retrieval, and data analysis. Because the field of correlative microscopy is relatively young, the capabilities of the various approaches have yet to be fully explored, and uncertainties remain when considering the best choice of strategy and workflow for the correlative experiment. With this in mind, the Journal of Physics D: Applied Physics presents a special roadmap on the correlative microscopy techniques, giving a comprehensive overview from various leading scientists in this field, via a collection of multiple short viewpoints.
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Affiliation(s)
- Toshio Ando
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Japan
| | | | | | - H Colin-York
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, United Kingdom
| | | | - Niels De Jonge
- INM-Leibniz Institute for New Materials, 66123 Saarbrücken, Germany
- Saarland University, 66123 Saarbrücken, Germany
| | - P J de Pablo
- Dpto. Física de la Materia Condensada Universidad Autónoma de Madrid 28049, Madrid, Spain
- Instituto de Física de la Materia Condensada IFIMAC, Universidad Autónoma de Madrid 28049, Madrid, Spain
| | - Elke Debroye
- KU Leuven, Department of Chemistry, B-3001 Heverlee, Belgium
| | - Christian Eggeling
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, United Kingdom
- Institute of Applied Optics, Friedrich-Schiller University, Jena, Germany
- Leibniz Institute of Photonic Technology (IPHT), Jena, Germany
| | - Christian Franck
- Department of Mechanical Engineering, University of Wisconsin-Madison, 1513 University Ave, Madison, WI 53706, United States of America
| | - Marco Fritzsche
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, United Kingdom
- Kennedy Institute for Rheumatology, University of Oxford, Oxford, United Kingdom
| | - Hans Gerritsen
- Debye Institute, Utrecht University, Utrecht, Netherlands
| | - Ben N G Giepmans
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Kay Grunewald
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Centre of Structural Systems Biology Hamburg and University of Hamburg, Hamburg, Germany
- Heinrich-Pette-Institute, Leibniz Institute of Virology, Hamburg, Germany
| | - Johan Hofkens
- KU Leuven, Department of Chemistry, B-3001 Heverlee, Belgium
| | | | | | - Rainer Kaufman
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Centre of Structural Systems Biology Hamburg and University of Hamburg, Hamburg, Germany
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Judith Klumpermann
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584CX Utrecht, Netherlands
| | - Nyoman Kurniawan
- Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD 4072, Australia
| | | | - Nalan Liv
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584CX Utrecht, Netherlands
| | - Viha Parekh
- Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Diana B Peckys
- Faculty of Medicine, Saarland University, 66421 Homburg, Germany
| | - Florian Rehfeldt
- University of Göttingen, Third Institute of Physics-Biophysics, 37077 Göttingen, Germany
| | - David C Reutens
- Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD 4072, Australia
| | | | - Tim Salditt
- University of Göttingen, Institute for X-Ray Physics, 37077 Göttingen, Germany
| | - Iwan A T Schaap
- SmarAct GmbH, Schütte-Lanz-Str. 9, D-26135 Oldenburg, Germany
| | - Ulrich S Schwarz
- Institute for Theoretical Physics and BioQuant, Heidelberg University, Heidelberg, Germany
| | - Paul Verkade
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Michael W Vogel
- Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Richard Wagner
- Department of Life Sciences & Chemistry, Jacobs University, Bremen, Germany
| | | | - Haifeng Yuan
- KU Leuven, Department of Chemistry, B-3001 Heverlee, Belgium
| | - Giovanni Zifarelli
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
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20
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Zifarelli G. A tale of two CLCs: biophysical insights toward understanding ClC-5 and ClC-7 function in endosomes and lysosomes. J Physiol 2015; 593:4139-50. [PMID: 26036722 DOI: 10.1113/jp270604] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Accepted: 05/22/2015] [Indexed: 11/08/2022] Open
Abstract
The CLC protein family comprises both Cl(-) channels and H(+) -coupled anion transporters. The understanding of the critical role of CLC proteins in a number of physiological functions has greatly contributed to a revision of the classical paradigm that attributed to Cl(-) ions only a marginal role in human physiology. The endosomal ClC-5 and the lysosomal ClC-7 are the best characterized human CLC transporters. Their dysfunction causes Dent's disease and osteopetrosis, respectively. It had been originally proposed that they would provide a Cl(-) shunt conductance allowing efficient acidification of intracellular compartments. However, this model seems to conflict with the transport properties of these proteins and with recent physiological evidence. Currently, there is no consensus on their specific physiological role. CLC proteins present also a number of peculiar biophysical properties, such as the dimeric architecture, the co-existence of intrinsically different thermodynamic modes of transport based on similar structural principles, and the gating mechanism recently emerging for the transporters, just to name a few. This review focuses on the biophysical properties and physiological roles of ClC-5 and ClC-7.
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Affiliation(s)
- Giovanni Zifarelli
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
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Kusch J, Zifarelli G. Patch-clamp fluorometry: electrophysiology meets fluorescence. Biophys J 2014; 106:1250-7. [PMID: 24655500 DOI: 10.1016/j.bpj.2014.02.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 12/23/2013] [Accepted: 02/06/2014] [Indexed: 12/26/2022] Open
Abstract
Ion channels and transporters are membrane proteins whose functions are driven by conformational changes. Classical biophysical techniques provide insight into either the structure or the function of these proteins, but a full understanding of their behavior requires a correlation of both these aspects in time. Patch-clamp and voltage-clamp fluorometry combine spectroscopic and electrophysiological techniques to simultaneously detect conformational changes and ionic currents across the membrane. Since its introduction, patch-clamp fluorometry has been responsible for invaluable advances in our knowledge of ion channel biophysics. Over the years, the technique has been applied to many different ion channel families to address several biophysical questions with a variety of spectroscopic approaches and electrophysiological configurations. This review illustrates the strength and the flexibility of patch-clamp fluorometry, demonstrating its potential as a tool for future research.
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Affiliation(s)
- Jana Kusch
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany.
| | - Giovanni Zifarelli
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Genova, Italy.
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Abstract
Cl(-) transport in animal cells has fundamental physiological roles and it is mediated by a variety of protein families, one of them being the CLC family of ion channels and transporters. Besides their physiological relevance, CLC proteins show peculiar biophysical properties. This review will focus on a member of the CLC protein family, the endosomal Cl(-)/H(+) antiporter ClC-5. ClC-5 mutations cause Dent's disease, a renal syndrome due to defective protein reabsorption in the proximal tubule. This established the critical function of ClC-5 for endocytosis. However, our understanding of ClC-5's molecular role in endosomes and of its biophysical properties has proved elusive in spite of important progress achieved in the last two decades. Early models in which ClC-5 would provide a shunt conductance to enable efficient endosomal acidification conflicted with the antiport activity of ClC-5 that has more recently emerged. Currently, the physiological role of ClC-5 is hotly debated and its biophysical properties are still not fully understood.
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Affiliation(s)
- Michael Pusch
- Istituto di Biofisica, CNR, Via De Marini 6, 16149 Genoa, Italy
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Gradogna A, Imbrici P, Zifarelli G, Liantonio A, Camerino DC, Pusch M. I-J loop involvement in the pharmacological profile of CLC-K channels expressed in Xenopus oocytes. Biochim Biophys Acta 2014; 1838:2745-56. [PMID: 25073071 PMCID: PMC4331650 DOI: 10.1016/j.bbamem.2014.07.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 07/13/2014] [Accepted: 07/21/2014] [Indexed: 12/19/2022]
Abstract
CLC-K chloride channels and their subunit, barttin, are crucial for renal NaCl reabsorption and for inner ear endolymph production. Mutations in CLC-Kb and barttin cause Bartter syndrome. Here, we identified two adjacent residues, F256 and N257, that when mutated hugely alter in Xenopus oocytes CLC-Ka's biphasic response to niflumic acid, a drug belonging to the fenamate class, with F256A being potentiated 37-fold and N257A being potently blocked with a KD~1μM. These residues are localized in the same extracellular I-J loop which harbors a regulatory Ca(2+) binding site. This loop thus can represent an ideal and CLC-K specific target for extracellular ligands able to modulate channel activity. Furthermore, we demonstrated the involvement of the barttin subunit in the NFA potentiation. Indeed the F256A mutation confers onto CLC-K1 a transient potentiation induced by NFA which is found only when CLC-K1/F256A is co-expressed with barttin. Thus, in addition to the role of barttin in targeting and gating, the subunit participates in the pharmacological modulation of CLC-K channels and thus represents a further target for potential drugs.
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Affiliation(s)
| | - Paola Imbrici
- Dipartimento di Farmacia-Scienze del farmaco, Università degli Studi di Bari, Via Orabona 4, 70125 Bari, Italy
| | | | - Antonella Liantonio
- Dipartimento di Farmacia-Scienze del farmaco, Università degli Studi di Bari, Via Orabona 4, 70125 Bari, Italy
| | - Diana Conte Camerino
- Dipartimento di Farmacia-Scienze del farmaco, Università degli Studi di Bari, Via Orabona 4, 70125 Bari, Italy
| | - Michael Pusch
- Istituto di Biofisica, CNR, Via De Marini 6, 16149 Genoa, Italy.
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Abstract
Cl(-) transport is of fundamental importance in the most diverse physiological contexts and it is mediated by a variety of ion channels and transporters belonging to different protein families. In particular, the recently identified TMEM16 protein family comprises the long sought Ca(2+)-activated Cl(-) channel (CaCC) and the activity of one of its members, TMEM16A, is highly dependent on temperature and is involved in thermal nociception. Among the other protein families mediating Cl(-) transport, CLC proteins are also regulated by temperature although so far the physiological implications of this dependence are unknown.
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Abstract
ClC-5 is a 2Cl−/1H+ antiporter highly expressed in endosomes of proximal tubule cells. It is essential for endocytosis and mutations in ClC-5 cause Dent's disease, potentially leading to renal failure. However, the physiological role of ClC-5 is still unclear. One of the main issues is whether the strong rectification of ClC-5 currents observed in heterologous systems, with currents elicited only at positive voltages, is preserved in vivo and what is the origin of this rectification. In this work we identified a ClC-5 mutation, D76H, which, besides the typical outward currents of the wild-type (WT), shows inward tail currents at negative potentials that allow the estimation of the reversal of ClC-5 currents for the first time. A detailed analysis of the dependence of these inward tail currents on internal and external pH and [Cl−] shows that they are generated by a coupled transport of Cl− and H+ with a 2 : 1 stoichiometry. From this result we conclude that the inward tail currents are caused by a gating mechanism that regulates ClC-5 transport activity and not by a major alteration of the transport mechanism itself. This implies that the strong rectification of the currents of WT ClC-5 is at least in part caused by a gating mechanism that activates the transporter at positive potentials. These results elucidate the biophysical properties of ClC-5 and contribute to the understanding of its physiological role.
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Affiliation(s)
- Silvia De Stefano
- G. Zifarelli: Istituto di Biofisica, CNR, Via De Marini 6, I-16149 Genova, Italy.
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Abstract
Despite the role of chloride channels and anion/proton antiporters of the CLC protein family in physiological processes and different genetic diseases, their pharmacology has been under-developed. In this issue of Chemistry & Biology, Howery et al. report the synthesis of 4'-octanamidostilbene-2,2'-disulfonate, the first high-affinity inhibitor of a CLC antiporter, a critical step toward reviving the CLC pharmacology.
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Abstract
Osteoporosis, characterized by excessive osteoclast mediated bone resorption, affects millions of people worldwide representing a major public health problem. ClC-7 is a chloride-proton exchanger localized in lysosomes and in the resorption lacuna in osteoclasts where it is essential for bone resorption. Thus, drugs targeted at ClC-7 have been proposed for ameliorating osteoporosis. However, functional assays suited for high throughput screening (HTS) of ClC-7 function are lacking. Here we describe two complementary variants of purely optical assays of the transport activity of ClC-7, redirected to the plasma membrane employing a genetically encoded fluorescent Cl−/pH indicator fused to the ClC-7 protein. These simple and robust functional assays of ClC-7 transport are well-suited to be applied in HTS of small-molecule inhibitors and may help to develop drugs suited for the treatment of osteoporosis.
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Affiliation(s)
- Ilaria Zanardi
- Istituto di Biofisica, CNR, Via De Marini 6, 16149 Genoa, Italy
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De Stefano S, Fiore M, Liantonio A, Conte Camerino D, Pusch M, Zifarelli G. Investigating a Benzofurane Derivative Binding Site on Human CLC-5. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.3092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Zifarelli G, De Stefano S, Zanardi I, Pusch M. On the mechanism of gating charge movement of ClC-5, a human Cl(-)/H(+) antiporter. Biophys J 2012; 102:2060-9. [PMID: 22824269 DOI: 10.1016/j.bpj.2012.03.067] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 03/28/2012] [Accepted: 03/29/2012] [Indexed: 10/28/2022] Open
Abstract
ClC-5 is a Cl(-)/H(+) antiporter that functions in endosomes and is important for endocytosis in the proximal tubule. The mechanism of transport coupling and voltage dependence in ClC-5 is unclear. Recently, a transport-deficient ClC-5 mutant (E268A) was shown to exhibit transient capacitive currents. Here, we studied the external and internal Cl(-) and pH dependence of the currents of E268A. Transient currents were almost completely independent of the intracellular pH. Even though the transient currents are modulated by extracellular pH, we could exclude that they are generated by proton-binding/unbinding reactions. In contrast, the charge movement showed a nontrivial dependence on external chloride, strongly supporting a model in which the movement of an intrinsic gating charge is followed by the voltage-dependent low-affinity binding of extracellular chloride ions. Mutation of the external Glu-211 (a residue implicated in the coupling of Cl(-) and proton transport) to aspartate abolished steady-state transport, but revealed transient currents that were shifted by ~150 mV to negative voltages compared to E268A. This identifies Glu(ext) as a major component of the gating charge underlying the transient currents of the electrogenic ClC-5 transporter. The molecular events underlying the transient currents of ClC-5 emerging from these results can be explained by an inward movement of the side chain of Glu(ext), followed by the binding of extracellular Cl(-) ions.
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Jeworutzki E, López-Hernández T, Capdevila-Nortes X, Sirisi S, Bengtsson L, Montolio M, Zifarelli G, Arnedo T, Müller CS, Schulte U, Nunes V, Martínez A, Jentsch TJ, Gasull X, Pusch M, Estévez R. GlialCAM, a protein defective in a leukodystrophy, serves as a ClC-2 Cl(-) channel auxiliary subunit. Neuron 2012; 73:951-61. [PMID: 22405205 PMCID: PMC3334819 DOI: 10.1016/j.neuron.2011.12.039] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2011] [Indexed: 11/30/2022]
Abstract
Ion fluxes mediated by glial cells are required for several physiological processes such as fluid homeostasis or the maintenance of low extracellular potassium during high neuronal activity. In mice, the disruption of the Cl− channel ClC-2 causes fluid accumulation leading to myelin vacuolation. A similar vacuolation phenotype is detected in humans affected with megalencephalic leukoencephalopathy with subcortical cysts (MLC), a leukodystrophy which is caused by mutations in MLC1 or GLIALCAM. We here identify GlialCAM as a ClC-2 binding partner. GlialCAM and ClC-2 colocalize in Bergmann glia, in astrocyte-astrocyte junctions at astrocytic endfeet around blood vessels, and in myelinated fiber tracts. GlialCAM targets ClC-2 to cell junctions, increases ClC-2 mediated currents, and changes its functional properties. Disease-causing GLIALCAM mutations abolish the targeting of the channel to cell junctions. This work describes the first auxiliary subunit of ClC-2 and suggests that ClC-2 may play a role in the pathology of MLC disease. Video Abstract
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Affiliation(s)
- Elena Jeworutzki
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genoa, Italy
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Abstract
Mammalian CLC proteins comprise both Cl− channels and Cl−/H+ antiporters that carry out fundamental physiological tasks by transporting Cl− across plasma membrane and intracellular compartments. The NO3− over Cl− preference of a plant CLC transporter has been pinpointed to a conserved serine residue located at Scen and it is generally assumed that the other two binding sites of CLCs, Sext and Sin, do not substantially contribute to anion selectivity. Here we show for the Cl−/H+ antiporter CLC-5 that the conserved and extracellularly exposed Lys210 residue is critical to determine the anion specificity for transport activity. In particular, mutations that neutralize or invert the charge at this position reverse the NO3− over Cl− preference of WT CLC-5 at a concentration of 100 mm, but do not modify the coupling stoichiometry with H+. The importance of the electrical charge is shown by chemical modification of K210C with positively charged cysteine-reactive compounds that reintroduce the WT preference for Cl−. At saturating extracellular anion concentrations, neutralization of Lys210 is of little impact on the anion preference, suggesting an important role of Lys210 on the association rate of extracellular anions to Sext.
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Affiliation(s)
| | - Michael Pusch
- Istituto di Biofisica, CNR, Via De Marini 6, I-16149 Genova, Italy
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Affiliation(s)
- Giovanni Zifarelli
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genoa, Italy
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Zifarelli G, Liantonio A, Gradogna A, Picollo A, Gramegna G, De Bellis M, Murgia AR, Babini E, Conte Camerino D, Pusch M. Identification of sites responsible for the potentiating effect of niflumic acid on ClC-Ka kidney chloride channels. Br J Pharmacol 2010; 160:1652-61. [PMID: 20649569 PMCID: PMC2936838 DOI: 10.1111/j.1476-5381.2010.00822.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 03/02/2010] [Accepted: 03/09/2010] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND AND PURPOSE ClC-K kidney Cl(-) channels are important for renal and inner ear transepithelial Cl(-) transport, and are potentially interesting pharmacological targets. They are modulated by niflumic acid (NFA), a non-steroidal anti-inflammatory drug, in a biphasic way: NFA activates ClC-Ka at low concentrations, but blocks the channel above approximately 1 mM. We attempted to identify the amino acids involved in the activation of ClC-Ka by NFA. EXPERIMENTAL APPROACH We used site-directed mutagenesis and two-electrode voltage clamp analysis of wild-type and mutant channels expressed in Xenopus oocytes. Guided by the crystal structure of a bacterial CLC homolog, we screened 97 ClC-Ka mutations for alterations of NFA effects. KEY RESULTS Mutations of five residues significantly reduced the potentiating effect of NFA. Two of these (G167A and F213A) drastically altered general gating properties and are unlikely to be involved in NFA binding. The three remaining mutants (L155A, G345S and A349E) severely impaired or abolished NFA potentiation. CONCLUSIONS AND IMPLICATIONS The three key residues identified (L155, G345, A349) are localized in two different protein regions that, based on the crystal structure of bacterial CLC homologs, are expected to be exposed to the extracellular side of the channel, relatively close to each other, and are thus good candidates for being part of the potentiating NFA binding site. Alternatively, the protein region identified mediates conformational changes following NFA binding. Our results are an important step towards the development of ClC-Ka activators for treating Bartter syndrome types III and IV with residual channel activity.
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Affiliation(s)
- G Zifarelli
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
| | - A Liantonio
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
- Sezione di Farmacologia, Dipartimento Farmacobiologico, Via Orabona 4, Università di BariBari, Italy
| | - A Gradogna
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
| | - A Picollo
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
| | - G Gramegna
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
- Sezione di Farmacologia, Dipartimento Farmacobiologico, Via Orabona 4, Università di BariBari, Italy
| | - M De Bellis
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
- Sezione di Farmacologia, Dipartimento Farmacobiologico, Via Orabona 4, Università di BariBari, Italy
| | - AR Murgia
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
| | - E Babini
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
| | - D Conte Camerino
- Sezione di Farmacologia, Dipartimento Farmacobiologico, Via Orabona 4, Università di BariBari, Italy
| | - M Pusch
- Istituto di Biofisica, Consiglio Nazionale delle RicercheGenova, Italy
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Zifarelli G, Pusch M. Intracellular regulation of human ClC-5 by adenine nucleotides. EMBO Rep 2009; 10:1111-6. [PMID: 19713962 DOI: 10.1038/embor.2009.159] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2009] [Revised: 05/26/2009] [Accepted: 06/18/2009] [Indexed: 11/09/2022] Open
Abstract
ClC-5, an endosomal Cl(-)/H(+) antiporter that is mutated in Dent disease, is essential for endosomal acidification and re-uptake of small molecular weight proteins in the renal proximal tubule. Eukaryotic chloride channels (CLCs) contain two cytoplasmic CBS domains, motifs present in different proteins, the function of which is still poorly understood. Structural studies have shown that ClC-5 can bind to ATP at the interface between the CBS domains, but so far the potential functional consequences of nucleotide binding to ClC-5 have not been investigated. Here, we show that the direct application of ATP, ADP and AMP in inside-out patch experiments potentiates the current mediated by ClC-5 with similar affinities. The nucleotides increase the probability of ClC-5 to be in an active, transporting state. The residues Tyr 617 and Asp 727, but not Ser 618, are crucial for the potentiation. These results provide a mechanistic and structural framework for the interpretation of nucleotide regulation of a CLC transporter.
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Affiliation(s)
- Giovanni Zifarelli
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Genova, Italy
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Pusch M, Zifarelli G. It's the proton also in ClC-2. J Physiol 2009; 587:1379-80. [PMID: 19336608 PMCID: PMC2678211 DOI: 10.1113/jphysiol.2009.169623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2024] Open
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Abstract
Some CLC proteins function as passive Cl− ion channels whereas others are secondary active chloride/proton antiporters. Voltage-dependent gating of the model Torpedo channel ClC-0 is modulated by intracellular and extracellular pH, possibly reflecting a mechanistic relationship with the chloride/proton coupling of CLC antiporters. We used inside-out patch clamp measurements and mutagenesis to explore the dependence of the fast gating mechanism of ClC-0 on intracellular pH and to identify the putative intracellular proton acceptor(s). Among the tested residues (S123, K129, R133, K149, E166, F214L, S224, E226, V227, C229, R305, R312, C415, H472, F418, V419, P420, and Y512) only mutants of E166, F214, and F418 qualitatively changed the pHint dependence. No tested amino acid emerged as a valid candidate for being a pH sensor. A detailed kinetic analysis of the dependence of fast gate relaxations on pHint and [Cl−]int provided quantitative constraints on possible mechanistic models of gating. In one particular model, a proton is generated by the dissociation of a water molecule in an intrapore chloride ion binding site. The proton is delivered to the side chain of E166 leading to the opening of the channel, while the hydroxyl ion is stabilized in the internal/central anion binding site. Deuterium isotope effects confirm that proton transfer is rate limiting for fast gate opening and that channel closure depends mostly on the concentration of OH− ions. The gating model is in natural agreement with the finding that only the closing rate constant, but not the opening rate constant, depends on pHint and [Cl−]int.
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Affiliation(s)
- Giovanni Zifarelli
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, I-16149 Genova, Italy
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Abstract
ClC-1 belongs to the gene family of CLC Cl− channels and Cl−/H+ antiporters. It is the major skeletal muscle chloride channel and is mutated in dominant and recessive myotonia. In addition to the membrane-embedded part, all mammalian CLC proteins possess a large cytoplasmic C-terminal domain that bears two so-called CBS (from cystathionine-β-synthase) domains. Several studies indicate that these domains might be involved in nucleotide binding and regulation. In particular, Bennetts et al. (J. Biol. Chem. 2005. 280:32452–32458) reported that the voltage dependence of hClC-1 expressed in HEK cells is regulated by intracellular ATP and other nucleotides. Moreover, very recently, Bennetts et al. (J. Biol. Chem. 2007. 282:32780–32791) and Tseng et al. (J. Gen. Physiol. 2007. 130:217–221) reported that the ATP effect was enhanced by intracellular acidification. Here, we show that in striking contrast with these findings, human ClC-1, expressed in Xenopus oocytes and studied with the inside-out configuration of the patch-clamp technique, is completely insensitive to intracellular ATP at concentrations up to 10 mM, at neutral pH (pH 7.3) as well as at slightly acidic pH (pH 6.2). These results have implications for a general understanding of nucleotide regulation of CLC proteins and for the physiological role of ClC-1 in muscle excitation.
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Zdebik AA, Zifarelli G, Bergsdorf EY, Soliani P, Scheel O, Jentsch TJ, Pusch M. Determinants of Anion-Proton Coupling in Mammalian Endosomal CLC Proteins. J Biol Chem 2008; 283:4219-27. [DOI: 10.1074/jbc.m708368200] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Abstract
H(+) ions are a substrate of many active and passive membrane transporters in all cells. Absolute proton fluxes are often quantified using intracellular pH sensitive microelectrodes or pH sensitive dyes. These measurements, however, rely on a priori estimates of the intracellular buffer capacity and on the assumption of diffusive equilibrium inside the cell. Here, assuming local equilibrium of protons with a single mobile buffer, we model the diffusion of H(+) in the extracellular medium around an H(+) pumping cell to estimate the expected pH changes as a function of time, distance from the cell, extracellular buffer capacity, and the absolute proton flux across the membrane. In particular, using accurate numerical simulation, we gauge the range of validity of an explicit, analytical solution of the linearized, nonstationary diffusion equation. Our results provide a framework to quantify the absolute membrane proton flux, if spatiotemporal information about the extracellular pH change is available, e.g., using imaging of pH dependent fluorescent dyes.
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Macías M, Teijido O, Zifarelli G, Martin P, Ramirez-Espain X, Zorzano A, Palacín M, Pusch M, Estévez R. Myotonia-related mutations in the distal C-terminus of ClC-1 and ClC-0 chloride channels affect the structure of a poly-proline helix. Biochem J 2007; 403:79-87. [PMID: 17107341 PMCID: PMC1828897 DOI: 10.1042/bj20061230] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Myotonia is a state of hyperexcitability of skeletal-muscle fibres. Mutations in the ClC-1 Cl- channel cause recessive and dominant forms of this disease. Mutations have been described throughout the protein-coding region, including three sequence variations (A885P, R894X and P932L) in a distal C-terminal stretch of residues [CTD (C-terminal domain) region] that are not conserved between CLC proteins. We show that surface expression of these mutants is reduced in Xenopus oocytes compared with wild-type ClC-1. Functional, biochemical and NMR spectroscopy studies revealed that the CTD region encompasses a segment conserved in most voltage-dependent CLC channels that folds with a secondary structure containing a short type II poly-proline helix. We found that the myotonia-causing mutation A885P disturbs this structure by extending the poly-proline helix. We hypothesize that this structural modification results in the observed alteration of the common gate that acts on both pores of the channel. We provide the first experimental investigation of structural changes resulting from myotonia-causing mutations.
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Affiliation(s)
- María J. Macías
- *Institut de Recerca Biomédica, Parc Científic de Barcelona, Josep Samitier 1-5, Barcelona, E-08028, Spain
| | - Oscar Teijido
- †Departament de Bioquímica i Biología Molecular, Facultat de Biologia, Universitat de Barcelona, Avda. Diagonal 645, Barcelona, E-08028, Spain
| | | | - Pau Martin
- *Institut de Recerca Biomédica, Parc Científic de Barcelona, Josep Samitier 1-5, Barcelona, E-08028, Spain
| | - Ximena Ramirez-Espain
- *Institut de Recerca Biomédica, Parc Científic de Barcelona, Josep Samitier 1-5, Barcelona, E-08028, Spain
| | - Antonio Zorzano
- *Institut de Recerca Biomédica, Parc Científic de Barcelona, Josep Samitier 1-5, Barcelona, E-08028, Spain
- †Departament de Bioquímica i Biología Molecular, Facultat de Biologia, Universitat de Barcelona, Avda. Diagonal 645, Barcelona, E-08028, Spain
| | - Manuel Palacín
- *Institut de Recerca Biomédica, Parc Científic de Barcelona, Josep Samitier 1-5, Barcelona, E-08028, Spain
- †Departament de Bioquímica i Biología Molecular, Facultat de Biologia, Universitat de Barcelona, Avda. Diagonal 645, Barcelona, E-08028, Spain
| | - Michael Pusch
- ‡Istituto di Biofisica, Via de Marini 6, I-16149 Genova, Italy
| | - Raúl Estévez
- *Institut de Recerca Biomédica, Parc Científic de Barcelona, Josep Samitier 1-5, Barcelona, E-08028, Spain
- †Departament de Bioquímica i Biología Molecular, Facultat de Biologia, Universitat de Barcelona, Avda. Diagonal 645, Barcelona, E-08028, Spain
- §ZMNH (Zentrum für Molekulare Neurobiologie Hamburg), Hamburg University, Falkenried 94, D-20246 Hamburg, Germany
- To whom correspondence should be addressed (email )
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Abstract
Chloride-transporting proteins play fundamental roles in many tissues in the plasma membrane as well as in intracellular membranes. They have received increasing attention in the last years because crucial, and often unexpected and novel, physiological functions have been disclosed with gene-targeting approaches, X-ray crystallography, and biophysical analysis. CLC proteins form a gene family that comprises nine members in mammals, at least four of which are involved in human genetic diseases. The X-ray structure of the bacterial CLC homolog, ClC-ec1, revealed a complex fold and confirmed the anticipated homodimeric double-barreled architecture of CLC-proteins with two separate Cl-ion transport pathways, one in each subunit. Four of the mammalian CLC proteins, ClC-1, ClC-2, ClC-Ka, and ClC-Kb, are chloride ion channels that fulfill their functional roles-stabilization of the membrane potential, transepithelial salt transport, and ion homeostasisin the plasma membrane. The other five CLC proteins are predominantly expressed in intracellular organelles like endosomes and lysosomes, where they are probably important for a proper luminal acidification, in concert with the V-type H+-ATPase. Surprisingly, ClC-4, ClC-5, and probably also ClC-3, are not Cl- ion channels but exhibit significant Cl-/H+ antiporter activity, as does the bacterial homolog ClC-ec1 and the plant homolog AtCLCa. The physiological significance of the Cl-/H+ antiport activity remains to be established.
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Affiliation(s)
- G Zifarelli
- CNR, Istituto di Biofisica, Via De Marini 6, 16149 Genova, Italy
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44
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Todt U, Dichgans M, Jurkat-Rott K, Heinze A, Zifarelli G, Koenderink JB, Goebel I, Zumbroich V, Stiller A, Ramirez A, Friedrich T, Göbel H, Kubisch C. Rare missense variants in ATP1A2 in families with clustering of common forms of migraine. Hum Mutat 2006; 26:315-21. [PMID: 16110494 DOI: 10.1002/humu.20229] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Migraine is a recurrent neurovascular disease. Its two most common forms-migraine without aura (MO) and migraine with aura (MA)-both show familial clustering and a complex pattern of inheritance. Familial hemiplegic migraine (FHM) is a rare monogenic subform caused by mutations in the calcium channel gene CACNA1A or the Na(+)/K(+)-ATPase gene ATP1A2. An involvement of FHM genes in the pathogenesis of common forms of migraine is not proven. We therefore systematically screened ATP1A2 in families with several members affected by MA and/or MO. We identified two novel missense alterations [c.520G>A (p.E174 K) and c.1544G>A (p.C515Y)] in two out of 45 families, which were not found in 520 control chromosomes. Functional studies of these variants in Xenopus oocytes by two-electrode voltage clamp measurements and radiochemical determination of ATPase activity showed that C515Y leads to a complete loss of function comparable with the effect of FHM-mutations whereas for E174 K no functional alteration could be found in the in vitro assays. In conclusion we propose that rare variants in ATP1A2 are involved in the susceptibility to common forms of migraine, because of 1) the absence of alterations in controls, 2) the particular pattern of segregation in both families, 3) the high conservation of mutated residues in Na(+)/K(+)-ATPases, 4) the functional effect of C515Y, and 5) the involvement of ATP1A2 in a monogenic form of migraine.
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Affiliation(s)
- Unda Todt
- Institut für Humangenetik, Universitätsklinikum Bonn, Bonn, Germany
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45
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Abstract
CLC Cl− channels are homodimers in which each subunit has a proper pore and a (fast) gate. An additional slow gate acts on both pores. A conserved glutamate (E166 in CLC-0) is a major determinant of gating in CLC-0 and is crucially involved in Cl−/H+ antiport of CLC-ec1, a CLC of known structure. We constructed tandem dimers with one wild-type (WT) and one mutant subunit (E166A or E166D) to show that these mutations of E166 specifically alter the fast gate of the pore to which they belong without effect on the fast gate of the neighboring pore. In addition both mutations activate the common slow gate. E166A pores have a large, voltage-independent open probability of the fast gate (popen), whereas popen of E166D pores is dramatically reduced. Similar to WT, popen of E166D was increased by lowering pHint. At negative voltages, E166D presents a persistent inward current that is blocked by p-chlorophenoxy-acetic acid (CPA) and increased at low pHext. The pHext dependence of the persistent current is analogous to a similar steady inward current in WT CLC-0. Surprisingly, however, the underlying unitary conductance of the persistent current in E166D is about an order of magnitude smaller than that of the transient deactivating inward Cl− current. Collectively, our data support the possibility that the mutated CLC-0 channel E166D can assume two distinct open states. Voltage-independent protonation of D166 from the outside favors a low conductance state, whereas protonation from the inside favors the high conductance state.
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Affiliation(s)
- Sonia Traverso
- Istituto di Biofisica, Consiglio Nazionale della Ricerche, Genova, Italy
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46
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Abstract
It was recently shown that the putative bacterial Cl- channel, ClC-ec1, is in reality a Cl--H+ antiporter. Our group has now shown that this is also the case for two human CLCs, ClC-4 and ClC-5. We found that the flux of Cl- in one direction is stoichiometrically coupled to the movement of protons in the opposite direction, unveiling a behaviour that is typical of a transporter rather than a channel. This discovery will surely stimulate further research to elucidate the molecular elements responsible for the behaviour as a transporter. On the physiological level, the antiport activity of ClC-4/ClC-5 must lead to a review of the role of CLC proteins in intracellular compartments. Small organic molecules have been extremely useful tools for studying ion channels and many commercial drugs target specific ion channel proteins. Several blockers have been found to inhibit the plasma membrane-localized CLC channels ClC-0, ClC-1 and ClC-Ka. These compounds include 9-anthracene-carboxylic acid (9-AC), p-chlorophenoxy-propionic acid (CPP) and its derivatives, and 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS). Two different binding sites have been identified, one extracellular and one intracellular. However, high-affinity ligands for most CLC proteins are still missing. Apart from being useful biophysical tools, such drugs may provide a way to modulate protein function in vivo. With these tasks to be accomplished, it is definitely an exciting time in the chloride transport field.
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Affiliation(s)
- M Pusch
- Istituto di biofisica, CNR, Via De Marini 6, I-16149 Genova, Italy.
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47
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Koenderink JB, Zifarelli G, Qiu LY, Schwarz W, De Pont JJHHM, Bamberg E, Friedrich T. Na,K-ATPase mutations in familial hemiplegic migraine lead to functional inactivation. Biochim Biophys Acta 2005; 1669:61-8. [PMID: 15843000 DOI: 10.1016/j.bbamem.2005.01.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2004] [Revised: 01/10/2005] [Accepted: 01/10/2005] [Indexed: 12/14/2022]
Abstract
The Na,K-ATPase is an ion-translocating transmembrane protein that actively maintains the electrochemical gradients for Na+ and K+ across the plasma membrane. The functional protein is a heterodimer comprising a catalytic alpha-subunit (four isoforms) and an ancillary beta-subunit (three isoforms). Mutations in the alpha2-subunit have recently been implicated in familial hemiplegic migraine type 2, but almost no thorough studies of the functional consequences of these mutations have been provided. We investigated the functional properties of the mutations L764P and W887R in the human Na,K-ATPase alpha2-subunit upon heterologous expression in Xenopus oocytes. No Na,K-ATPase-specific pump currents could be detected in cells expressing these mutants. The binding of radiolabelled [3H]ouabain to intact cells suggested that this could be due to a lack of plasma membrane expression. However, plasma membrane isolation showed that the mutated pumps are well expressed at the plasma membrane. 86Rb+-flux and ATPase activity measurements demonstrated that the mutants are inactive. Therefore, the primary disease-causing mechanism is loss-of-function of the Na,K-ATPase alpha2-isoform.
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Affiliation(s)
- Jan B Koenderink
- Department of Biochemistry, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500HB Nijmegen, The Netherlands
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48
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Geibel S, Zimmermann D, Zifarelli G, Becker A, Koenderink JB, Hu YK, Kaplan JH, Friedrich T, Bamberg E. Conformational dynamics of Na+/K+- and H+/K+-ATPase probed by voltage clamp fluorometry. Ann N Y Acad Sci 2003; 986:31-8. [PMID: 12763772 DOI: 10.1111/j.1749-6632.2003.tb07136.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We used the method of site-directed fluorescence labeling in combination with voltage-clamp fluorometry for time-resolved recording of localized conformational transitions of the Na(+)/K(+)- and H(+)/K(+)-ATPase. Therefore, single cysteine mutations were introduced into the extracellular TM5-TM6 loop of the sheep Na(+)/K(+)-ATPase alpha(1)-subunit devoid of other extracellular cysteines. Upon expression in Xenopus oocytes and covalent attachment of tetramethylrhodamine-maleimide (TMRM) as a reporter fluorophore, Cys-mutant N790C showed large fluorescence changes of up to 5% in response to extracellular K(+) that were completely abolished by ouabain. When voltage jumps were applied under Na(+)/Na(+)-exchange conditions, we observed fluorescence changes that paralleled the transient currents originating from the E(1)P<-->E(2)P transition. These fluorescence changes were also completely inhibited by ouabain, as were the voltage jump-induced transient currents. Transient fluorescence changes could also be measured as a function of increasing K(+) concentrations, that is, under turnover conditions. As a result, the distribution between E(1) and E(2) states can be determined at any time and membrane potential. Very similar fluorescence signals were obtained for rat gastric H(+)/K(+)-ATPase upon expression in oocytes, when a single cysteine was introduced at a position homologous to N790 in Na(+)/K(+)-ATPase for attachment of the fluorophore. As to the high sequence similarity among P-type ATPases within the TM5 helix and the TM5-TM6 loop region, our results enable new means of kinetic investigation for these pumps under physiological conditions in living cells.
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Affiliation(s)
- Sven Geibel
- Max-Planck-Institute of Biophysics, Kennedyallee 70, D-60596 Frankfurt/M., Germany
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