1
|
Leca I, Phillips AW, Ushakova L, Cushion TD, Keays DA. Codon modification of Tuba1a alters mRNA levels and causes a severe neurodevelopmental phenotype in mice. Sci Rep 2023; 13:1215. [PMID: 36681692 PMCID: PMC9867703 DOI: 10.1038/s41598-023-27782-2] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 01/09/2023] [Indexed: 01/22/2023] Open
Abstract
The tubulinopathies are an umbrella of rare diseases that result from mutations in tubulin genes and are frequently characterised by severe brain malformations. The characteristics of a given disease reflect the expression pattern of the transcript, the function of a given tubulin gene, and the role microtubules play in a particular cell type. Mouse models have proved to be valuable tools that have provided insight into the molecular and cellular mechanisms that underlie the disease state. In this manuscript we compare two Tuba1a mouse models, both of which express wild-type TUBA1A protein but employ different codon usage. We show that modification of the Tuba1a mRNA sequence results in homozygous lethality and a severe neurodevelopmental phenotype. This is associated with a decrease in the number of post-mitotic neurons, PAX6 positive progenitors, and an increase in the number of apoptotic cells. We attribute this to a decrease in the stability of the modified Tuba1a transcript, and the absence of compensation by the other neurogenic tubulins. Our findings highlight the importance of maintaining the wild-type coding sequence when engineering mouse lines and the impact of synonymous genetic variation.
Collapse
Affiliation(s)
- Ines Leca
- Vienna Biocenter (VBC), Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Alexander William Phillips
- Vienna Biocenter (VBC), Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
- Department of Biology, Ludwig-Maximilians-University Munich, 82152, Planegg-Martinsried, Germany
| | - Lyubov Ushakova
- Vienna Biocenter (VBC), Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Thomas David Cushion
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3EG, UK
| | - David Anthony Keays
- Vienna Biocenter (VBC), Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria.
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3EG, UK.
- Department of Biology, Ludwig-Maximilians-University Munich, 82152, Planegg-Martinsried, Germany.
| |
Collapse
|
2
|
Leca I, Phillips AW, Hofer I, Landler L, Ushakova L, Cushion TD, Dürnberger G, Stejskal K, Mechtler K, Keays DA. A proteomic survey of microtubule-associated proteins in a R402H TUBA1A mutant mouse. PLoS Genet 2020; 16:e1009104. [PMID: 33137126 PMCID: PMC7660477 DOI: 10.1371/journal.pgen.1009104] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 11/12/2020] [Accepted: 09/08/2020] [Indexed: 11/25/2022] Open
Abstract
Microtubules play a critical role in multiple aspects of neurodevelopment, including the generation, migration and differentiation of neurons. A recurrent mutation (R402H) in the α-tubulin gene TUBA1A is known to cause lissencephaly with cerebellar and striatal phenotypes. Previous work has shown that this mutation does not perturb the chaperone-mediated folding of tubulin heterodimers, which are able to assemble and incorporate into the microtubule lattice. To explore the molecular mechanisms that cause the disease state we generated a new conditional mouse line that recapitulates the R402H variant. We show that heterozygous mutants present with laminar phenotypes in the cortex and hippocampus, as well as a reduction in striatal size and cerebellar abnormalities. We demonstrate that homozygous expression of the R402H allele causes neuronal death and exacerbates a cell intrinsic defect in cortical neuronal migration. Microtubule sedimentation assays coupled with quantitative mass spectrometry demonstrated that the binding and/or levels of multiple microtubule associated proteins (MAPs) are perturbed by the R402H mutation including VAPB, REEP1, EZRIN, PRNP and DYNC1l1/2. Consistent with these data we show that the R402H mutation impairs dynein-mediated transport which is associated with a decoupling of the nucleus to the microtubule organising center. Our data support a model whereby the R402H variant is able to fold and incorporate into microtubules, but acts as a gain of function by perturbing the binding of MAPs. Microtubules are polymers composed of tubulin proteins, which play an important role in the development of the human brain. Genetic mutations in tubulin genes are known to cause neurodevelopmental diseases, including lissencephaly which is characterised by an impairment in the migration of neurons. In this study we investigate how a common mutation (R402H) in TUBA1A causes lissencephaly by generating and characterising a mouse with the same variant. We show that affected animals recapitulate multiple aspects of the human disease; including laminar perturbations in the cortex and hippocampus, attributable to defects in neuronal migration at key developmental time points. To characterize the molecular implications of the R402H mutation we purified microtubules from the developing brain, and analysed the proteins present by mass spectrometry. This revealed that the binding of DYNC1I1/2 to microtubules is altered in mice with the R402H mutation. Our results provide insight into the molecular pathology underlying tubulin related disease states, and provide a foundation for the rational design of therapeutic interventions.
Collapse
Affiliation(s)
- Ines Leca
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | | | - Iris Hofer
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Lukas Landler
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
- Institute of Zoology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Lyubov Ushakova
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Thomas David Cushion
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Gerhard Dürnberger
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna, Austria
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Vienna, Austria
| | - Karel Stejskal
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Vienna, Austria
| | - Karl Mechtler
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna, Austria
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Vienna, Austria
| | - David Anthony Keays
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Australia
- Division of Neurobiology, Department Biology II, Ludwig-Maximilians-University Munich, Planegg-Martinsried 82152, Germany
- * E-mail:
| |
Collapse
|
3
|
Nordmann GC, Malkemper EP, Landler L, Ushakova L, Nimpf S, Heinen R, Schuechner S, Ogris E, Keays DA. A high sensitivity ZENK monoclonal antibody to map neuronal activity in Aves. Sci Rep 2020; 10:915. [PMID: 31969617 PMCID: PMC6976653 DOI: 10.1038/s41598-020-57757-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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: 08/07/2019] [Accepted: 12/20/2019] [Indexed: 01/04/2023] Open
Abstract
The transcription factor ZENK is an immediate early gene that has been employed as a surrogate marker to map neuronal activity in the brain. It has been used in a wide variety of species, however, commercially available antibodies have limited immunoreactivity in birds. To address this issue we generated a new mouse monoclonal antibody, 7B7-A3, raised against ZENK from the rock pigeon (Columba livia). We show that 7B7-A3 labels clZENK in both immunoblots and histological stainings with high sensitivity and selectivity for its target. Using a sound stimulation paradigm we demonstrate that 7B7-A3 can detect activity-dependent ZENK expression at key stations of the central auditory pathway of the pigeon. Finally, we compare staining efficiency across three avian species and confirm that 7B7-A3 is compatible with immunohistochemical detection of ZENK in the rock pigeon, zebra finch, and domestic chicken. Taken together, 7B7-A3 represents a useful tool for the avian neuroscience community to map functional activity in the brain.
Collapse
Affiliation(s)
- Gregory Charles Nordmann
- Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Erich Pascal Malkemper
- Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Lukas Landler
- Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Lyubov Ushakova
- Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Simon Nimpf
- Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Robert Heinen
- Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Stefan Schuechner
- Monoclonal Antibody Facility, Max Perutz Labs, Medical University of Vienna, Dr. Bohr-Gasse 9, 1030, Vienna, Austria
| | - Egon Ogris
- Monoclonal Antibody Facility, Max Perutz Labs, Medical University of Vienna, Dr. Bohr-Gasse 9, 1030, Vienna, Austria
| | - David Anthony Keays
- Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria.
| |
Collapse
|
4
|
Nimpf S, Nordmann GC, Kagerbauer D, Malkemper EP, Landler L, Papadaki-Anastasopoulou A, Ushakova L, Wenninger-Weinzierl A, Novatchkova M, Vincent P, Lendl T, Colombini M, Mason MJ, Keays DA. A Putative Mechanism for Magnetoreception by Electromagnetic Induction in the Pigeon Inner Ear. Curr Biol 2019; 29:4052-4059.e4. [DOI: 10.1016/j.cub.2019.09.048] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/28/2019] [Accepted: 09/19/2019] [Indexed: 11/16/2022]
|
5
|
Tripathy R, Leca I, van Dijk T, Weiss J, van Bon BW, Sergaki MC, Gstrein T, Breuss M, Tian G, Bahi-Buisson N, Paciorkowski AR, Pagnamenta AT, Wenninger-Weinzierl A, Martinez-Reza MF, Landler L, Lise S, Taylor JC, Terrone G, Vitiello G, Del Giudice E, Brunetti-Pierri N, D'Amico A, Reymond A, Voisin N, Bernstein JA, Farrelly E, Kini U, Leonard TA, Valence S, Burglen L, Armstrong L, Hiatt SM, Cooper GM, Aldinger KA, Dobyns WB, Mirzaa G, Pierson TM, Baas F, Chelly J, Cowan NJ, Keays DA. Mutations in MAST1 Cause Mega-Corpus-Callosum Syndrome with Cerebellar Hypoplasia and Cortical Malformations. Neuron 2018; 100:1354-1368.e5. [PMID: 30449657 PMCID: PMC6436622 DOI: 10.1016/j.neuron.2018.10.044] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [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: 10/11/2017] [Revised: 05/03/2018] [Accepted: 10/24/2018] [Indexed: 01/04/2023]
Abstract
Corpus callosum malformations are associated with a broad range of neurodevelopmental diseases. We report that de novo mutations in MAST1 cause mega-corpus-callosum syndrome with cerebellar hypoplasia and cortical malformations (MCC-CH-CM) in the absence of megalencephaly. We show that MAST1 is a microtubule-associated protein that is predominantly expressed in post-mitotic neurons and is present in both dendritic and axonal compartments. We further show that Mast1 null animals are phenotypically normal, whereas the deletion of a single amino acid (L278del) recapitulates the distinct neurological phenotype observed in patients. In animals harboring Mast1 microdeletions, we find that the PI3K/AKT3/mTOR pathway is unperturbed, whereas Mast2 and Mast3 levels are diminished, indicative of a dominant-negative mode of action. Finally, we report that de novo MAST1 substitutions are present in patients with autism and microcephaly, raising the prospect that mutations in this gene give rise to a spectrum of neurodevelopmental diseases.
Collapse
Affiliation(s)
- Ratna Tripathy
- Research Institute of Molecular Pathology, Campus Vienna Biocenter 1, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Ines Leca
- Research Institute of Molecular Pathology, Campus Vienna Biocenter 1, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Tessa van Dijk
- Department of Clinical Genetics, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Janneke Weiss
- Amsterdam UMC, Vrije Universiteit Amsterdam, Clinical Genetics, De Boelelaan 1117, Amsterdam, the Netherlands
| | - Bregje W van Bon
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Maria Christina Sergaki
- Research Institute of Molecular Pathology, Campus Vienna Biocenter 1, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Thomas Gstrein
- Research Institute of Molecular Pathology, Campus Vienna Biocenter 1, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Martin Breuss
- Department of Neurosciences, Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Guoling Tian
- Department of Biochemistry & Molecular Pharmacology, NYU Langone Medical Center, New York, NY 10016, USA
| | - Nadia Bahi-Buisson
- Université Paris Descartes, Institut Cochin Hôpital Cochin, 75014 Paris, France
| | | | - Alistair T Pagnamenta
- NIHR Oxford Biomedical Research Centre, Oxford, UK, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Andrea Wenninger-Weinzierl
- Research Institute of Molecular Pathology, Campus Vienna Biocenter 1, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Maria Fernanda Martinez-Reza
- Research Institute of Molecular Pathology, Campus Vienna Biocenter 1, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Lukas Landler
- Research Institute of Molecular Pathology, Campus Vienna Biocenter 1, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Stefano Lise
- NIHR Oxford Biomedical Research Centre, Oxford, UK, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Jenny C Taylor
- NIHR Oxford Biomedical Research Centre, Oxford, UK, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Gaetano Terrone
- Department of Translational Medical Sciences, Section of Pediatrics, Federico II University, 80131 Naples, Italy
| | - Giuseppina Vitiello
- Department of Translational Medical Sciences, Section of Pediatrics, Federico II University, 80131 Naples, Italy
| | - Ennio Del Giudice
- Department of Translational Medical Sciences, Section of Pediatrics, Federico II University, 80131 Naples, Italy
| | - Nicola Brunetti-Pierri
- Department of Translational Medical Sciences, Section of Pediatrics, Federico II University, 80131 Naples, Italy; Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Naples, Italy
| | - Alessandra D'Amico
- Department of Advanced Medical Sciences, University of Naples Federico II, 80131 Naples, Italy
| | - Alexandre Reymond
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Norine Voisin
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | | | | | - Usha Kini
- Department of Clinical Genetics, Oxford Regional Genetics Service, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Thomas A Leonard
- Center for Medical Biochemistry, Medical University of Vienna, Max F. Perutz Laboratories, Vienna Biocenter (VBC), Campus Vienna Biocenter 5, 1030 Vienna, Austria
| | - Stéphanie Valence
- Centre de référence des Malformations et Maladies Congénitales du Cervelet et Département de Génétique et Embryologie Médicale, APHP, Hôpital Trousseau, 75012 Paris, France
| | - Lydie Burglen
- Centre de référence des Malformations et Maladies Congénitales du Cervelet et Département de Génétique et Embryologie Médicale, APHP, Hôpital Trousseau, 75012 Paris, France
| | - Linlea Armstrong
- Provincial Medical Genetics Programme, BCWH and Department of Medical Genetics, University of British Columbia, Vancouver, BC V6H 3N1, Canada
| | - Susan M Hiatt
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA
| | - Gregory M Cooper
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA
| | - Kimberly A Aldinger
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA 98101, USA
| | - William B Dobyns
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA 98101, USA
| | - Ghayda Mirzaa
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA 98101, USA
| | - Tyler Mark Pierson
- Departments of Pediatrics and Neurology & the Board of Governors Regenerative Medicine, Institute Cedars Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Frank Baas
- Department of Clinical Genetics, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Jamel Chelly
- Service de Diagnostic Génétique, Hôpital Civil de Strasbourg, Hôpitaux Universitaires de Strasbourg, 67091 Strasbourg, France
| | - Nicholas J Cowan
- Department of Biochemistry & Molecular Pharmacology, NYU Langone Medical Center, New York, NY 10016, USA
| | - David Anthony Keays
- Research Institute of Molecular Pathology, Campus Vienna Biocenter 1, Vienna Biocenter (VBC), Vienna 1030, Austria.
| |
Collapse
|
6
|
Engels S, Treiber CD, Salzer MC, Michalik A, Ushakova L, Keays DA, Mouritsen H, Heyers D. Lidocaine is a nocebo treatment for trigeminally mediated magnetic orientation in birds. J R Soc Interface 2018; 15:20180124. [PMID: 30089685 PMCID: PMC6127160 DOI: 10.1098/rsif.2018.0124] [Citation(s) in RCA: 9] [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: 02/19/2018] [Accepted: 07/13/2018] [Indexed: 12/30/2022] Open
Abstract
Even though previously described iron-containing structures in the upper beak of pigeons were almost certainly macrophages, not magnetosensitive neurons, behavioural and neurobiological evidence still supports the involvement of the ophthalmic branch of the trigeminal nerve (V1) in magnetoreception. In previous behavioural studies, inactivation of putative V1-associated magnetoreceptors involved either application of the surface anaesthetic lidocaine to the upper beak or sectioning of V1. Here, we compared the effects of lidocaine treatment, V1 ablations and sham ablations on magnetic field-driven neuronal activation in V1-recipient brain regions in European robins. V1 sectioning led to significantly fewer Egr-1-expressing neurons in the trigeminal brainstem than in the sham-ablated birds, whereas lidocaine treatment had no effect on neuronal activation. Furthermore, Prussian blue staining showed that nearly all iron-containing cells in the subepidermal layer of the upper beak are nucleated and are thus not part of the trigeminal nerve, and iron-containing cells appeared in highly variable numbers at inconsistent locations between individual robins and showed no systematic colocalization with a neuronal marker. Our data suggest that lidocaine treatment has been a nocebo to the birds and a placebo for the experimenters. Currently, the nature and location of any V1-associated magnetosensor remains elusive.
Collapse
Affiliation(s)
- Svenja Engels
- AG Neurosensorics, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | | | | | - Andreas Michalik
- AG Neurosensorics, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | | | | | - Henrik Mouritsen
- AG Neurosensorics, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | - Dominik Heyers
- AG Neurosensorics, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| |
Collapse
|
7
|
Lange L, Pagnamenta AT, Lise S, Clasper S, Stewart H, Akha ES, Quaghebeur G, Knight SJL, Keays DA, Taylor JC, Kini U. A de novo frameshift in HNRNPK causing a Kabuki-like syndrome with nodular heterotopia. Clin Genet 2016; 90:258-62. [PMID: 26954065 PMCID: PMC5006848 DOI: 10.1111/cge.12773] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 02/26/2016] [Accepted: 03/03/2016] [Indexed: 01/23/2023]
Abstract
Kabuki syndrome is a heterogeneous condition characterized by distinctive facial features, intellectual disability, growth retardation, skeletal abnormalities and a range of organ malformations. Although at least two major causative genes have been identified, these do not explain all cases. Here we describe a patient with a complex Kabuki-like syndrome that included nodular heterotopia, in whom testing for several single-gene disorders had proved negative. Exome sequencing uncovered a de novo c.931_932insTT variant in HNRNPK (heterogeneous nuclear ribonucleoprotein K). Although this variant was identified in March 2012, its clinical relevance could only be confirmed following the August 2015 publication of two cases with HNRNPK mutations and an overlapping phenotype that included intellectual disability, distinctive facial dysmorphism and skeletal/connective tissue abnormalities. Whilst we had attempted (unsuccessfully) to identify additional cases through existing collaborators, the two published cases were 'matched' using GeneMatcher, a web-based tool for connecting researchers and clinicians working on identical genes. Our report therefore exemplifies the importance of such online tools in clinical genetics research and the benefits of periodically reviewing cases with variants of unproven significance. Our study also suggests that loss of function variants in HNRNPK should be considered as a molecular basis for patients with Kabuki-like syndrome.
Collapse
Affiliation(s)
- L Lange
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - A T Pagnamenta
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - S Lise
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - S Clasper
- Oxford Regional Genetics Service, Oxford Radcliffe Hospitals NHS Trust, The Churchill Hospital, Oxford, UK
| | - H Stewart
- Department of Clinical Genetics, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - E S Akha
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - G Quaghebeur
- Department of Neuroradiology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - S J L Knight
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - D A Keays
- Institute of Molecular Pathology, Vienna, Austria
| | - J C Taylor
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - U Kini
- Department of Clinical Genetics, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| |
Collapse
|
8
|
Ngo L, Haas M, Qu Z, Li SS, Zenker J, Teng KSL, Gunnersen JM, Breuss M, Habgood M, Keays DA, Heng JIT. TUBB5 and its disease-associated mutations influence the terminal differentiation and dendritic spine densities of cerebral cortical neurons. Hum Mol Genet 2014; 23:5147-58. [PMID: 24833723 DOI: 10.1093/hmg/ddu238] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The microtubule cytoskeleton is critical for the generation and maturation of neurons in the developing mammalian nervous system. We have previously shown that mutations in the β-tubulin gene TUBB5 cause microcephaly with structural brain abnormalities in humans. While it is known that TUBB5 is necessary for the proper generation and migration of neurons, little is understood of the role it plays in neuronal differentiation and connectivity. Here, we report that perturbations to TUBB5 disrupt the morphology of cortical neurons, their neuronal complexity, axonal outgrowth, as well as the density and shape of dendritic spines in the postnatal murine cortex. The features we describe are consistent with defects in synaptic signaling. Cellular-based assays have revealed that TUBB5 substitutions have the capacity to alter the dynamic properties and polymerization rates of the microtubule cytoskeleton. Together, our studies show that TUBB5 is essential for neuronal differentiation and dendritic spine formation in vivo, providing insight into the underlying cellular pathology associated with TUBB5 disease states.
Collapse
Affiliation(s)
- Linh Ngo
- EMBL Australia, The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Matilda Haas
- EMBL Australia, The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Zhengdong Qu
- EMBL Australia, The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Shan Shan Li
- EMBL Australia, The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Jennifer Zenker
- EMBL Australia, The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Kathleen Sue Lyn Teng
- The Anatomy and Neuroscience Department, University of Melbourne, Parkville, VIC 3010, Australia
| | - Jenny Margaret Gunnersen
- The Anatomy and Neuroscience Department, University of Melbourne, Parkville, VIC 3010, Australia The Florey Institute of Neuroscience and Mental Health, Parkville, VIC 3010, Australia
| | - Martin Breuss
- Institute of Molecular Pathology, Dr Bohr-Gasse, Vienna 1030, Austria
| | - Mark Habgood
- The Anatomy and Neuroscience Department, University of Melbourne, Parkville, VIC 3010, Australia
| | | | - Julian Ik-Tsen Heng
- EMBL Australia, The Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia,
| |
Collapse
|
9
|
Treiber CD, Salzer M, Breuss M, Ushakova L, Lauwers M, Edelman N, Keays DA. High resolution anatomical mapping confirms the absence of a magnetic sense system in the rostral upper beak of pigeons. Commun Integr Biol 2013; 6:e24859. [PMID: 23940826 PMCID: PMC3738016 DOI: 10.4161/cib.24859] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 04/26/2013] [Accepted: 04/29/2013] [Indexed: 11/22/2022] Open
Abstract
The cells that are responsible for detecting magnetic fields in animals remain undiscovered. Previous studies have proposed that pigeons employ a magnetic sense system that consists of six bilateral patches of magnetite containing dendrites located in the rostral subepidermis of the upper beak. We have challenged this hypothesis arguing that clusters of iron-rich cells in this region are macrophages, not magnetosensitive neurons. Here we present additional data in support of this conclusion. We have undertaken high resolution anatomical mapping of iron-rich cells in the rostral upper beak of pigeons, excluding the possibility that a conserved six-loci magnetic sense system exists. In addition we have extended our immunohistochemical studies to a second cohort of pigeons, confirming that iron rich cells in the upper beak are positive for MHCII and CD44, which are expressed by macrophages. We argue that it is important to critically assess conclusions that have been made in the past, while keeping an open mind as the search for the magnetoreceptor continues.
Collapse
|
10
|
Breuss M, Heng JIT, Poirier K, Tian G, Jaglin XH, Qu Z, Braun A, Gstrein T, Ngo L, Haas M, Bahi-Buisson N, Moutard ML, Passemard S, Verloes A, Gressens P, Xie Y, Robson KJH, Rani DS, Thangaraj K, Clausen T, Chelly J, Cowan NJ, Keays DA. Mutations in the β-tubulin gene TUBB5 cause microcephaly with structural brain abnormalities. Cell Rep 2012; 2:1554-62. [PMID: 23246003 PMCID: PMC3595605 DOI: 10.1016/j.celrep.2012.11.017] [Citation(s) in RCA: 137] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 07/18/2012] [Accepted: 11/21/2012] [Indexed: 01/11/2023] Open
Abstract
The formation of the mammalian cortex requires the generation, migration, and differentiation of neurons. The vital role that the microtubule cytoskeleton plays in these cellular processes is reflected by the discovery that mutations in various tubulin isotypes cause different neurodevelopmental diseases, including lissencephaly (TUBA1A), polymicrogyria (TUBA1A, TUBB2B, TUBB3), and an ocular motility disorder (TUBB3). Here, we show that Tubb5 is expressed in neurogenic progenitors in the mouse and that its depletion in vivo perturbs the cell cycle of progenitors and alters the position of migrating neurons. We report the occurrence of three microcephalic patients with structural brain abnormalities harboring de novo mutations in TUBB5 (M299V, V353I, and E401K). These mutant proteins, which affect the chaperone-dependent assembly of tubulin heterodimers in different ways, disrupt neurogenic division and/or migration in vivo. Our results provide insight into the functional repertoire of the tubulin gene family, specifically implicating TUBB5 in embryonic neurogenesis and microcephaly.
Collapse
Affiliation(s)
- Martin Breuss
- Institute of Molecular Pathology, Dr Bohr-Gasse, Vienna 1030, Austria
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Treiber CD, Salzer MC, Riegler J, Edelman N, Sugar C, Breuss M, Pichler P, Cadiou H, Saunders M, Lythgoe M, Shaw J, Keays DA. Clusters of iron-rich cells in the upper beak of pigeons are macrophages not magnetosensitive neurons. Nature 2012; 484:367-70. [DOI: 10.1038/nature11046] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Accepted: 03/19/2012] [Indexed: 11/10/2022]
|
12
|
Edwards A, Treiber CD, Breuss M, Pidsley R, Huang GJ, Cleak J, Oliver PL, Flint J, Keays DA. Cytoarchitectural disruption of the superior colliculus and an enlarged acoustic startle response in the Tuba1a mutant mouse. Neuroscience 2011; 195:191-200. [PMID: 21875651 PMCID: PMC3188702 DOI: 10.1016/j.neuroscience.2011.08.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 08/10/2011] [Accepted: 08/17/2011] [Indexed: 12/17/2022]
Abstract
The Jenna mutant mouse harbours an S140G mutation in Tuba1a that impairs tubulin heterodimer formation resulting in defective neuronal migration during development. The consequence of decreased neuronal motility is a fractured pyramidal cell layer in the hippocampus and wave-like perturbations in the cerebral cortex. Here, we extend our characterisation of this mouse investigating the laminar architecture of the superior colliculus (SC). Our results reveal that the structure of the SC in mutant animals is intact; however, it is significantly thinner with an apparent fusion of the intermediate grey and white layers. Birthdate labelling at E12.5 and E13.5 showed that the S140G mutation impairs the radial migration of neurons in the SC. A quantitative assessment of neuronal number in adulthood reveals a massive reduction in postmitotic neurons in mutant animals, which we attribute to increased apoptotic cell death. Consistent with the role of the SC in modulating sensorimotor gating, and the circuitry that modulates this behaviour, we find that Jenna mutants exhibit an exaggerated acoustic startle response. Our results highlight the importance of Tuba1a for correct neuronal migration and implicate postnatal apoptotic cell death in the pathophysiological mechanisms underlying the tubulinopathies.
Collapse
Affiliation(s)
- A Edwards
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Jaglin XH, Poirier K, Saillour Y, Buhler E, Tian G, Bahi-Buisson N, Fallet-Bianco C, Phan-Dinh-Tuy F, Kong XP, Bomont P, Castelnau-Ptakhine L, Odent S, Loget P, Kossorotoff M, Snoeck I, Plessis G, Parent P, Beldjord C, Cardoso C, Represa A, Flint J, Keays DA, Cowan NJ, Chelly J. Mutations in the beta-tubulin gene TUBB2B result in asymmetrical polymicrogyria. Nat Genet 2009; 41:746-52. [PMID: 19465910 DOI: 10.1038/ng.380] [Citation(s) in RCA: 295] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Accepted: 03/09/2009] [Indexed: 01/08/2023]
Abstract
Polymicrogyria is a relatively common but poorly understood defect of cortical development characterized by numerous small gyri and a thick disorganized cortical plate lacking normal lamination. Here we report de novo mutations in a beta-tubulin gene, TUBB2B, in four individuals and a 27-gestational-week fetus with bilateral asymmetrical polymicrogyria. Neuropathological examination of the fetus revealed an absence of cortical lamination associated with the presence of ectopic neuronal cells in the white matter and in the leptomeningeal spaces due to breaches in the pial basement membrane. In utero RNAi-based inactivation demonstrates that TUBB2B is required for neuronal migration. We also show that two disease-associated mutations lead to impaired formation of tubulin heterodimers. These observations, together with previous data, show that disruption of microtubule-based processes underlies a large spectrum of neuronal migration disorders that includes not only lissencephaly and pachygyria, but also polymicrogyria malformations.
Collapse
|
14
|
Yalcin B, Fullerton J, Miller S, Keays DA, Brady S, Bhomra A, Jefferson A, Volpi E, Copley RR, Flint J, Mott R. Unexpected complexity in the haplotypes of commonly used inbred strains of laboratory mice. Proc Natl Acad Sci U S A 2004; 101:9734-9. [PMID: 15210992 PMCID: PMC470780 DOI: 10.1073/pnas.0401189101] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [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] [Received: 02/20/2004] [Indexed: 01/21/2023] Open
Abstract
Investigation of sequence variation in common inbred mouse strains has revealed a segmented pattern in which regions of high and low variant density are intermixed. Furthermore, it has been suggested that allelic strain distribution patterns also occur in well defined blocks and consequently could be used to map quantitative trait loci (QTL) in comparisons between inbred strains. We report a detailed analysis of polymorphism distribution in multiple inbred mouse strains over a 4.8-megabase region containing a QTL influencing anxiety. Our analysis indicates that it is only partly true that the genomes of inbred strains exist as a patchwork of segments of sequence identity and difference. We show that the definition of haplotype blocks is not robust and that methods for QTL mapping may fail if they assume a simple block-like structure.
Collapse
Affiliation(s)
- B Yalcin
- Wellcome Trust Centre for Human Genetics, Oxford University, Roosevelt Drive, Oxford OX3 7BN, United Kingdom
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Sandall DW, Satkunanathan N, Keays DA, Polidano MA, Liping X, Pham V, Down JG, Khalil Z, Livett BG, Gayler KR. A novel alpha-conotoxin identified by gene sequencing is active in suppressing the vascular response to selective stimulation of sensory nerves in vivo. Biochemistry 2003; 42:6904-11. [PMID: 12779345 DOI: 10.1021/bi034043e] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.1] [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: 11/28/2022]
Abstract
We describe the identification of a conopeptide sequence in venom duct mRNA from Conus victoriae that suppresses a vascular response to pain in the rat. PCR-RACE was used to screen venom duct cDNAs for those transcripts that encode specific antagonists of vertebrate neuronal nicotinic acetylcholine receptors (nAChRs). One of these peptides, Vc1.1, was active as an antagonist of neuronal nAChRs in receptor binding and functional studies in bovine chromaffin cells. It also suppressed the vascular responses to unmyelinated sensory nerve C-fiber activation in rats. Such vascular responses are involved in pain transmission. Furthermore, its ability to suppress C-fiber function was greater than that of MVIIA, an omega-conotoxin with known analgesic activity in rats and humans. Vc1.1 has a high degree of sequence similarity to the alpha-conotoxin family of peptides and has the 4,7 loop structure characteristic of the subfamily of peptides that act on neuronal-type nAChRs. The results suggest that neuronal alpha-conotoxins should be further investigated with respect to their potential to suppress pain.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Cattle
- Chromaffin Cells/drug effects
- Chromaffin Cells/metabolism
- Conotoxins/genetics
- Conotoxins/pharmacology
- DNA, Complementary/genetics
- Dose-Response Relationship, Drug
- Male
- Molecular Sequence Data
- Nerve Fibers, Unmyelinated/drug effects
- Nerve Fibers, Unmyelinated/physiology
- Neuromuscular Junction/drug effects
- Neuromuscular Junction/physiology
- Neurons, Afferent/drug effects
- Neurons, Afferent/physiology
- Nicotinic Antagonists/pharmacology
- Polymerase Chain Reaction/methods
- RNA, Messenger/genetics
- Rats
- Rats, Sprague-Dawley
- Receptors, Nicotinic/physiology
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- omega-Conotoxins/pharmacology
Collapse
Affiliation(s)
- D W Sandall
- Department of Biochemistry and Molecular Biology and National Ageing Research Institute, The University of Melbourne, Victoria 3010, Australia
| | | | | | | | | | | | | | | | | | | |
Collapse
|