1
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Ipsen MB, Sørensen EMG, Thomsen EA, Weiss S, Haldrup J, Dalby A, Palmfeldt J, Bross P, Rasmussen M, Fredsøe J, Klingenberg S, Jochumsen MR, Bouchelouche K, Ulhøi BP, Borre M, Mikkelsen JG, Sørensen KD. A genome-wide CRISPR-Cas9 knockout screen identifies novel PARP inhibitor resistance genes in prostate cancer. Oncogene 2022; 41:4271-4281. [PMID: 35933519 DOI: 10.1038/s41388-022-02427-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 07/07/2022] [Accepted: 07/26/2022] [Indexed: 11/10/2022]
Abstract
DNA repair gene mutations are frequent in castration-resistant prostate cancer (CRPC), suggesting eligibility for poly(ADP-ribose) polymerase inhibitor (PARPi) treatment. However, therapy resistance is a major clinical challenge and genes contributing to PARPi resistance are poorly understood. Using a genome-wide CRISPR-Cas9 knockout screen, this study aimed at identifying genes involved in PARPi resistance in CRPC. Based on the screen, we identified PARP1, and six novel candidates associated with olaparib resistance upon knockout. For validation, we generated multiple knockout populations/clones per gene in C4 and/or LNCaP CRPC cells, which confirmed that loss of PARP1, ARH3, YWHAE, or UBR5 caused olaparib resistance. PARP1 or ARH3 knockout caused cross-resistance to other PARPis (veliparib and niraparib). Furthermore, PARP1 or ARH3 knockout led to reduced autophagy, while pharmacological induction of autophagy partially reverted their PARPi resistant phenotype. Tumor RNA sequencing of 126 prostate cancer patients identified low ARH3 expression as an independent predictor of recurrence. Our results advance the understanding of PARPi response by identifying four novel genes that contribute to PARPi sensitivity in CRPC and suggest a new model of PARPi resistance through decreased autophagy.
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Affiliation(s)
- Malene Blond Ipsen
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Ea Marie Givskov Sørensen
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | | | - Simone Weiss
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Jakob Haldrup
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Johan Palmfeldt
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Peter Bross
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Martin Rasmussen
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Jacob Fredsøe
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Søren Klingenberg
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Nuclear Medicine and PET-Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Mads R Jochumsen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Nuclear Medicine and PET-Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Kirsten Bouchelouche
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Nuclear Medicine and PET-Centre, Aarhus University Hospital, Aarhus, Denmark
| | | | - Michael Borre
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Karina Dalsgaard Sørensen
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark. .,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
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2
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Lane A, Hunter K, Lee EL, Hyman D, Bross P, Alabd A, Betchen M, Terrigno V, Talwar S, Ricketti D, Shenker B, Clyde T, Roberts BW. Clinical characteristics and symptom duration among outpatients with COVID-19. Am J Infect Control 2022; 50:383-389. [PMID: 34780804 PMCID: PMC8590478 DOI: 10.1016/j.ajic.2021.10.039] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 01/08/2023]
Abstract
BACKGROUND Approximately 80% of people with COVID-19 do not require hospitalization. Studies examining the outpatient experience have not tracked symptoms to resolution leading to unknown expected symptom duration. Our objectives were to (1) determine symptom duration among patients with COVID-19 who do not require hospitalization and (2) identify potential risk factors associated with prolonged symptom duration. DESIGN This is a retrospective cohort study conducted across an academic healthcare system including adult patients with laboratory-confirmed SARS-CoV-2 infection between March 18th and April 28th, 2020 who were not hospitalized. Symptom duration encompassed time from patient-reported symptom onset as documented in the chart until documented symptom resolution. We calculated the median symptom duration and tested if demographics, comorbidities, or reported symptoms were associated with symptom duration. KEY RESULTS Of 294 patients meeting inclusion criteria, 178 (60.5%) had documented symptom resolution. The median [interquartile range (IQR)] symptom duration for included patients was 15 (8-24) days. No associations were found between comorbidities and symptom duration. Factors associated with prolonged symptom duration were presence vs lack of lower respiratory symptoms [median (IQR) 16.5 (10.75-33.5) vs 14.5 (7-21.75) days respectively, P < .001] and neurologic symptoms [median (IQR) 17 (9-28) vs 9.5 (4-17) days, P < .001] at disease onset. CONCLUSIONS The median symptom duration in outpatients is 15 days and over 25% of patients have symptoms longer than 21 days.
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Affiliation(s)
- Alexandra Lane
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ.
| | - Krystal Hunter
- Cooper Research Institute, Cooper Medical School of Rowan University, Camden, NJ
| | - Elizabeth Leilani Lee
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Daniel Hyman
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Peter Bross
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Andrew Alabd
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Melanie Betchen
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Vittorio Terrigno
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Shikha Talwar
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Daniel Ricketti
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Bennett Shenker
- Department of Family Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Thomas Clyde
- Department of Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
| | - Brian W Roberts
- Department of Emergency Medicine, Cooper University Health Care, Cooper Medical School of Rowan University, One Cooper Plaza, Camden, NJ
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3
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Pearson AD, Rossig C, Mackall C, Shah NN, Baruchel A, Reaman G, Ricafort R, Heenen D, Bassan A, Berntgen M, Bird N, Bleickardt E, Bouchkouj N, Bross P, Brownstein C, Cohen SB, de Rojas T, Ehrlich L, Fox E, Gottschalk S, Hanssens L, Hawkins DS, Horak ID, Taylor DH, Johnson C, Karres D, Ligas F, Ludwinski D, Mamonkin M, Marshall L, Masouleh BK, Matloub Y, Maude S, McDonough J, Minard-Colin V, Norga K, Nysom K, Pappo A, Pearce L, Pieters R, Pule M, Quintás-Cardama A, Richardson N, Schüßler-Lenz M, Scobie N, Sersch MA, Smith MA, Sterba J, Tasian SK, Weigel B, Weiner SL, Zwaan CM, Lesa G, Vassal G. Paediatric Strategy Forum for medicinal product development of chimeric antigen receptor T-cells in children and adolescents with cancer: ACCELERATE in collaboration with the European Medicines Agency with participation of the Food and Drug Administration. Eur J Cancer 2021; 160:112-133. [PMID: 34840026 DOI: 10.1016/j.ejca.2021.10.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [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: 09/28/2021] [Accepted: 10/13/2021] [Indexed: 12/30/2022]
Abstract
The seventh multi-stakeholder Paediatric Strategy Forum focused on chimeric antigen receptor (CAR) T-cells for children and adolescents with cancer. The development of CAR T-cells for patients with haematological malignancies, especially B-cell precursor acute lymphoblastic leukaemia (BCP-ALL), has been spectacular. However, currently, there are scientific, clinical and logistical challenges for use of CAR T-cells in BCP-ALL and other paediatric malignancies, particularly in acute myeloid leukaemia (AML), lymphomas and solid tumours. The aims of the Forum were to summarise the current landscape of CAR T-cell therapy development in paediatrics, too identify current challenges and future directions, with consideration of other immune effector modalities and ascertain the best strategies to accelerate their development and availability to children. Although the effect is of limited duration in about half of the patients, anti-CD19 CAR T-cells produce high response rates in relapsed/refractory BCP-ALL and this has highlighted previously unknown mechanisms of relapse. CAR T-cell treatment as first- or second-line therapy could also potentially benefit patients whose disease has high-risk features associated with relapse and failure of conventional therapies. Identifying patients with very early and early relapse in whom CAR T-cell therapy may replace haematopoietic stem cell transplantation and be definitive therapy versus those in whom it provides a more effective bridge to haematopoietic stem cell transplantation is a very high priority. Development of approaches to improve persistence, either by improving T cell fitness or using more humanised/fully humanised products and co-targeting of multiple antigens to prevent antigen escape, could potentially further optimise therapy. Many differences exist between paediatric B-cell non-Hodgkin lymphomas (B-NHL) and BCP-ALL. In view of the very small patient numbers with relapsed lymphoma, careful prioritisation is needed to evaluate CAR T-cells in children with Burkitt lymphoma, primary mediastinal B cell lymphoma and other NHL subtypes. Combination trials of alternative targets to CD19 (CD20 or CD22) should also be explored as a priority to improve efficacy in this population. Development of CD30 CAR T-cell immunotherapy strategies in patients with relapsed/refractory Hodgkin lymphoma will likely be most efficiently accomplished by joint paediatric and adult trials. CAR T-cell approaches are early in development for AML and T-ALL, given the unique challenges of successful immunotherapy actualisation in these diseases. At this time, CD33 and CD123 appear to be the most universal targets in AML and CD7 in T-ALL. The results of ongoing or planned first-in-human studies are required to facilitate further understanding. There are promising early results in solid tumours, particularly with GD2 targeting cell therapies in neuroblastoma and central nervous system gliomas that represent significant unmet clinical needs. Further understanding of biology is critical to success. The comparative benefits of autologous versus allogeneic CAR T-cells, T-cells engineered with T cell receptors T-cells engineered with T cell receptor fusion constructs, CAR Natural Killer (NK)-cell products, bispecific T-cell engager antibodies and antibody-drug conjugates require evaluation in paediatric malignancies. Early and proactive academia and multi-company engagement are mandatory to advance cellular immunotherapies in paediatric oncology. Regulatory advice should be sought very early in the design and preparation of clinical trials of innovative medicines, for which regulatory approval may ultimately be sought. Aligning strategic, scientific, regulatory, health technology and funding requirements from the inception of a clinical trial is especially important as these are very expensive therapies. The model for drug development for cell therapy in paediatric oncology could also involve a 'later stage handoff' to industry after early development in academic hands. Finally, and very importantly, strategies must evolve to ensure appropriate ease of access for children who need and could potentially benefit from these therapies.
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Affiliation(s)
| | - Claudia Rossig
- University Children´s Hospital Muenster, Pediatric Hematology and Oncology, Germany
| | - Crystal Mackall
- Department of Pediatrics and Medicine, Stanford University, Center for Cancer Cell Therapy, Stanford Cancer Institute, Stanford, CA, USA
| | - Nirali N Shah
- Pediatric Oncology Branch, National Cancer Institute, USA
| | - Andre Baruchel
- Hôpital Universitaire Robert Debré (APHP) and Université de Paris, France
| | | | | | | | | | - Michael Berntgen
- Scientific Evidence Generation Department, Human Medicines Division, European Medicines Agency (EMA), Amsterdam, Netherlands
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Dominik Karres
- Paediatric Medicines Office, Scientific Evidence Generation Department, Human Medicines Division, European Medicines Agency (EMA), Amsterdam, Netherlands
| | - Franca Ligas
- Paediatric Medicines Office, Scientific Evidence Generation Department, Human Medicines Division, European Medicines Agency (EMA), Amsterdam, Netherlands
| | | | | | - Lynley Marshall
- The Royal Marsden Hospital and the Institute of Cancer Research, London, UK
| | | | | | - Shannon Maude
- Children's Hospital of Philadelphia and University of Pennsylvania School of Medicine, Philadelphia, USA
| | | | - Veronique Minard-Colin
- Department of Pediatric and Adolescent Oncology, INSERM U1015, Gustave Roussy, Université Paris-Saclay, Villejuif, France
| | - Koen Norga
- Antwerp University Hospital, Paediatric Committee of the European Medicines Agency, Federal Agency for Medicines and Health Products, Belgium
| | | | | | | | - Rob Pieters
- Princess Maxima Center for Pediatric Oncology, Netherlands
| | | | | | | | - Martina Schüßler-Lenz
- Chair of CAT (Committee for Advanced Therapies), European Medicines Agency (EMA), Amsterdam, Netherlands; Paul-Ehrlich-Institut, Germany
| | | | | | | | - Jaroslav Sterba
- University Hospital Brno, Masaryk University, Brno, Czech Republic
| | - Sarah K Tasian
- Children's Hospital of Philadelphia and University of Pennsylvania School of Medicine, Philadelphia, USA
| | | | | | - Christian Michel Zwaan
- Princess Maxima Center for Pediatric Oncology, Netherlands; Haematological Malignancies Co-Chair Innovative Therapies for Children with Cancer Consortium (ITCC), Europe; Erasmus University Medical Center Rotterdam, Netherlands
| | - Giovanni Lesa
- Paediatric Medicines Office, Scientific Evidence Generation Department, Human Medicines Division, European Medicines Agency (EMA), Amsterdam, Netherlands
| | - Gilles Vassal
- ACCELERATE, Europe; Department of Pediatric and Adolescent Oncology, Gustave Roussy, Université Paris-Saclay, Villejuif, France
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4
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Farup J, Just J, de Paoli F, Lin L, Jensen JB, Billeskov T, Roman IS, Cömert C, Møller AB, Madaro L, Groppa E, Fred RG, Kampmann U, Gormsen LC, Pedersen SB, Bross P, Stevnsner T, Eldrup N, Pers TH, Rossi FMV, Puri PL, Jessen N. Human skeletal muscle CD90 + fibro-adipogenic progenitors are associated with muscle degeneration in type 2 diabetic patients. Cell Metab 2021; 33:2201-2214.e11. [PMID: 34678202 PMCID: PMC9165662 DOI: 10.1016/j.cmet.2021.10.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [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: 02/04/2021] [Revised: 04/29/2021] [Accepted: 10/01/2021] [Indexed: 01/12/2023]
Abstract
Type 2 diabetes mellitus (T2DM) is associated with impaired skeletal muscle function and degeneration of the skeletal muscles. However, the mechanisms underlying the degeneration are not well described in human skeletal muscle. Here we show that skeletal muscle of T2DM patients exhibit degenerative remodeling of the extracellular matrix that is associated with a selective increase of a subpopulation of fibro-adipogenic progenitors (FAPs) marked by expression of THY1 (CD90)-the FAPCD90+. We identify platelet-derived growth factor (PDGF) as a key FAP regulator, as it promotes proliferation and collagen production at the expense of adipogenesis. FAPsCD90+ display a PDGF-mimetic phenotype, with high proliferative activity, clonogenicity, and production of extracellular matrix. FAPCD90+ proliferation was reduced by in vitro treatment with metformin. Furthermore, metformin treatment reduced FAP content in T2DM patients. These data identify a PDGF-driven conversion of a subpopulation of FAPs as a key event in the fibrosis development in T2DM muscle.
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Affiliation(s)
- Jean Farup
- Department of Biomedicine, Aarhus University, Aarhus 8000, Denmark; Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus 8200, Denmark; Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus 8200, Denmark.
| | - Jesper Just
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus 8200, Denmark; Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus 8200, Denmark
| | - Frank de Paoli
- Department of Biomedicine, Aarhus University, Aarhus 8000, Denmark; Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Lin Lin
- Department of Biomedicine, Aarhus University, Aarhus 8000, Denmark; Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Jonas Brorson Jensen
- Department of Biomedicine, Aarhus University, Aarhus 8000, Denmark; Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Tine Billeskov
- Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus 8200, Denmark; Diabetes and Hormonal Diseases, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Ines Sanchez Roman
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus 8000, Denmark; Department of Psychology, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, Madrid 28670, Spain
| | - Cagla Cömert
- Molecular Research Unit, Department of Clinical Medicine, Aarhus University, Aarhus 8200, Denmark
| | - Andreas Buch Møller
- Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus 8200, Denmark; Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Luca Madaro
- Department of AHFMO, University of Rome "la Sapienza," Rome 00185, Italy
| | - Elena Groppa
- The University of British Columbia, Vancouver BC CA V6T, Canada
| | - Rikard Göran Fred
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Ulla Kampmann
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Lars C Gormsen
- Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Steen B Pedersen
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus 8200, Denmark; Diabetes and Hormonal Diseases, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Peter Bross
- Molecular Research Unit, Department of Clinical Medicine, Aarhus University, Aarhus 8200, Denmark
| | - Tinna Stevnsner
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus 8000, Denmark
| | - Nikolaj Eldrup
- Department of Vascular Surgery, Rigshospitalet, Copenhagen 2100, Denmark
| | - Tune H Pers
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Fabio M V Rossi
- The University of British Columbia, Vancouver BC CA V6T, Canada
| | - Pier Lorenzo Puri
- Sanford-Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Niels Jessen
- Department of Biomedicine, Aarhus University, Aarhus 8000, Denmark; Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus 8200, Denmark; Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus 8200, Denmark; Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus 8200, Denmark.
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5
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Henriques BJ, Katrine Jentoft Olsen R, Gomes CM, Bross P. Electron transfer flavoprotein and its role in mitochondrial energy metabolism in health and disease. Gene 2021; 776:145407. [PMID: 33450351 DOI: 10.1016/j.gene.2021.145407] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 12/08/2020] [Accepted: 12/16/2020] [Indexed: 12/15/2022]
Abstract
Electron transfer flavoprotein (ETF) is an enzyme with orthologs from bacteria to humans. Human ETF is nuclear encoded by two separate genes, ETFA and ETFB, respectively. After translation, the two subunits are imported to the mitochondrial matrix space and assemble into a heterodimer containing one FAD and one AMP as cofactors. ETF functions as a hub taking up electrons from at least 14 flavoenzymes, feeding them into the respiratory chain. This represents a major source of reducing power for the electron transport chain from fatty acid oxidation and amino acid degradation. Transfer of electrons from the donor enzymes to ETF occurs by direct transfer between the enzyme bound flavins, a process that is tightly regulated by the polypeptide chain and by protein:protein interactions. ETF, in turn relays electrons to the iron sulfur cluster of the inner membrane protein ETF:QO, from where they travel via the FAD in ETF:QO to ubiquinone, entering the respiratory chain at the level of complex III. ETF recognizes its dehydrogenase partners via a recognition loop that anchors the protein on its partner followed by dynamic movements of the ETF flavin domain that bring redox cofactors in close proximity, thus promoting electron transfer. Genetic mutations in the ETFA or ETFB genes cause the Mendelian disorder multiple acyl-CoA dehydrogenase deficiency (MADD; OMIM #231680). We here review the knowledge on human ETF and investigations of the effects of disease-associated missense mutations in this protein that have promoted the understanding of the essential role that ETF plays in cellular metabolism and human disease.
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Affiliation(s)
- Bárbara J Henriques
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
| | - Rikke Katrine Jentoft Olsen
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, 8200 Aarhus, Denmark.
| | - Cláudio M Gomes
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
| | - Peter Bross
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, 8200 Aarhus, Denmark.
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6
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Carlsen J, Cömert C, Bross P, Palmfeldt J. Optimized High-Contrast Brightfield Microscopy Application for Noninvasive Proliferation Assays of Human Cell Cultures. Assay Drug Dev Technol 2020; 18:215-225. [PMID: 32692633 DOI: 10.1089/adt.2020.981] [Citation(s) in RCA: 2] [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] [Indexed: 11/13/2022] Open
Abstract
High-contrast brightfield (HCBF) microscopy has emerged as a strong tool for noninvasive counting of cells in culture. HCBF imaging delivers precise cell growth data and is completely label free rendering it an attractive alternative to common cell counting procedures that often adversely affect cell growth. With computational image analysis, HCBF achieves efficient high-throughput automated workflows, extremely relevant for drug and chemical screens in pharmaceutical, toxicological, and biomedical research. We demonstrate the applicability of HCBF microscopy to count three common cell types (HEK293, Huh7, and primary human dermal fibroblasts) with diverse morphology challenging the method. The three cell types required different analysis settings, and we identified two parameters of the computational image analysis, which after cell-specific optimization significantly improved the cell counting accuracy, namely the lower size limit and the intensity threshold. Three-dimensional (3D) imaging approaches, which have obtained great attention in recent years, were an interesting prospect to combine with HCBF microscopy. We optimized the analysis of two 3D outputs but found 3D HCBF imaging to be inferior to the optimized single-layer HCBF imaging for cell counting. HCBF cell counts were highly linearly correlated with (R2 > 0.99) and highly similar (<15% difference) to cell counts obtained through Hoechst staining, over a broad range of densities allowing at least this level of accuracy for two to three cell generations in Huh7 cells and fibroblasts. Counts of HEK293 cells correlated somewhat less. In conclusion, the HCBF cell counting method is excellently suited for cell proliferation assays and cytotoxicity assays.
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Affiliation(s)
- Jasper Carlsen
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Aarhus N, Denmark
| | - Cagla Cömert
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Aarhus N, Denmark
| | - Peter Bross
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Aarhus N, Denmark
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Aarhus N, Denmark
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7
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Cömert C, Brick L, Ang D, Palmfeldt J, Meaney BF, Kozenko M, Georgopoulos C, Fernandez-Guerra P, Bross P. A recurrent de novo HSPD1 variant is associated with hypomyelinating leukodystrophy. Cold Spring Harb Mol Case Stud 2020; 6:mcs.a004879. [PMID: 32532876 PMCID: PMC7304351 DOI: 10.1101/mcs.a004879] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [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: 12/20/2019] [Accepted: 03/23/2020] [Indexed: 12/02/2022] Open
Abstract
Standardization of the use of next-generation sequencing for the diagnosis of rare neurological disorders has made it possible to detect potential disease-causing genetic variations, including de novo variants. However, the lack of a clear pathogenic relevance of gene variants poses a critical limitation for translating this genetic information into clinical practice, increasing the necessity to perform functional assays. Genetic screening is currently recommended in the guidelines for diagnosis of hypomyelinating leukodystrophies (HLDs). HLDs represent a group of rare heterogeneous disorders that interfere with the myelination of the neurons in the central nervous system. One of the HLD-related genes is HSPD1, encoding the mitochondrial chaperone heat shock protein 60 (HSP60), which functions as folding machinery for the mitochondrial proteins imported into the mitochondrial matrix space. Disease-causing HSPD1 variants have been associated with an autosomal recessive form of fatal hypomyelinating leukodystrophy (HLD4, MitCHAP60 disease; MIM #612233) and an autosomal dominant form of spastic paraplegia, type 13 (SPG13; MIM #605280). In 2018, a de novo HSPD1 variant was reported in a patient with HLD. Here, we present another case carrying the same heterozygous de novo variation in the HSPD1 gene (c.139T > G, p.Leu47Val) associated with an HLD phenotype. Our molecular studies show that the variant HSP60 protein is stably present in the patient's fibroblasts, and functional assays demonstrate that the variant protein lacks in vivo function, thus confirming its disease association. We conclude that de novo variations of the HSPD1 gene should be considered as potentially disease-causing in the diagnosis and pathogenesis of the HLDs.
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Affiliation(s)
- Cagla Cömert
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Lauren Brick
- Division of Genetics, McMaster Children's Hospital, Hamilton, Ontario L8S 4K1, Canada
| | - Debbie Ang
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112-5650, USA
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Brandon F Meaney
- Division of Pediatric Neurology, McMaster Children's Hospital, Hamilton, Ontario L8S 4K1, Canada
| | - Mariya Kozenko
- Division of Genetics, McMaster Children's Hospital, Hamilton, Ontario L8S 4K1, Canada
| | - Costa Georgopoulos
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112-5650, USA
| | - Paula Fernandez-Guerra
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Peter Bross
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, 8200, Aarhus N, Denmark
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8
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Bie AS, Cömert C, Körner R, Corydon TJ, Palmfeldt J, Hipp MS, Hartl FU, Bross P. An inventory of interactors of the human HSP60/HSP10 chaperonin in the mitochondrial matrix space. Cell Stress Chaperones 2020; 25:407-416. [PMID: 32060690 PMCID: PMC7192978 DOI: 10.1007/s12192-020-01080-6] [Citation(s) in RCA: 6] [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: 12/09/2019] [Revised: 01/14/2020] [Accepted: 02/10/2020] [Indexed: 10/25/2022] Open
Abstract
The HSP60/HSP10 chaperonin assists folding of proteins in the mitochondrial matrix space by enclosing them in its central cavity. The chaperonin forms part of the mitochondrial protein quality control system. It is essential for cellular survival and mutations in its subunits are associated with rare neurological disorders. Here we present the first survey of interactors of the human mitochondrial HSP60/HSP10 chaperonin. Using a protocol involving metabolic labeling of HEK293 cells, cross-linking, and immunoprecipitation of HSP60, we identified 323 interacting proteins. As expected, the vast majority of these proteins are localized to the mitochondrial matrix space. We find that approximately half of the proteins annotated as mitochondrial matrix proteins interact with the HSP60/HSP10 chaperonin. They cover a broad spectrum of functions and metabolic pathways including the mitochondrial protein synthesis apparatus, the respiratory chain, and mitochondrial protein quality control. Many of the genes encoding HSP60 interactors are annotated as disease genes. There is a correlation between relative cellular abundance and relative abundance in the HSP60 immunoprecipitates. Nineteen abundant matrix proteins occupy more than 60% of the HSP60/HSP10 chaperonin capacity. The reported inventory of interactors can form the basis for interrogating which proteins are especially dependent on the chaperonin.
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Affiliation(s)
- Anne Sigaard Bie
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark
| | - Cagla Cömert
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark
| | - Roman Körner
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany
| | - Thomas J Corydon
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, 8000, Aarhus C, Denmark
- Department of Ophthalmology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark
| | - Mark S Hipp
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands
- School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, 26111, Oldenburg, Germany
| | - F Ulrich Hartl
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany
| | - Peter Bross
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark.
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9
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Cömert C, Fernandez-Guerra P, Bross P. A Cell Model for HSP60 Deficiencies: Modeling Different Levels of Chaperonopathies Leading to Oxidative Stress and Mitochondrial Dysfunction. Methods Mol Biol 2019; 1873:225-239. [PMID: 30341613 DOI: 10.1007/978-1-4939-8820-4_14] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Besides providing the majority of ATP production in cells, mitochondria are also involved in many other cellular functions and are central for cellular stress signaling. Mitochondrial dysfunction induces not only inherited mitochondrial disorders but also contributes to neurodegenerative diseases, cancer, diabetes, and metabolic syndrome. The HSP60/HSP10 molecular chaperone complex facilitates folding of mitochondrial proteins and is thus an important factor for many mitochondrial functions. To model different degrees of oxidative stress and mitochondrial dysfunction we here describe a HEK293 derived Flp-In cell system with stable insertion and tunable expression of HSP60 cDNA carrying a dominant negative mutation. When expressed the dominant negative HSP60 mutant is incorporated into endogenously encoded HSP60/HSP10 complexes and impairs chaperone activity of the HSP60/HSP10 complex in a dose dependent manner. Using this system, different levels of oxidative stress and mitochondrial dysfunction challenges can be generated depending on the induction level of the mutant HSP60 cDNA insert. Here we describe our system and pertinent analysis methodology for use in studies of mitochondrial chaperone deficiency and resulting effects of increased production of reactive oxygen species and mitochondrial dysfunction.
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Affiliation(s)
- Cagla Cömert
- Research Unit for Molecular Medicine, Department of Clinical Medicine, HEALTH, Aarhus University, and Department of Clinical Biochemistry Aarhus University Hospital, Aarhus, Denmark
- Department of Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Paula Fernandez-Guerra
- Research Unit for Molecular Medicine, Department of Clinical Medicine, HEALTH, Aarhus University, and Department of Clinical Biochemistry Aarhus University Hospital, Aarhus, Denmark
- Department of Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Peter Bross
- Research Unit for Molecular Medicine, Department of Clinical Medicine, HEALTH, Aarhus University, and Department of Clinical Biochemistry Aarhus University Hospital, Aarhus, Denmark.
- Department of Biochemistry, Aarhus University Hospital, Aarhus, Denmark.
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10
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Sahebekhtiari N, Fernandez-Guerra P, Nochi Z, Carlsen J, Bross P, Palmfeldt J. Deficiency of the mitochondrial sulfide regulator ETHE1 disturbs cell growth, glutathione level and causes proteome alterations outside mitochondria. Biochim Biophys Acta Mol Basis Dis 2018; 1865:126-135. [PMID: 30391543 DOI: 10.1016/j.bbadis.2018.10.035] [Citation(s) in RCA: 12] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 10/14/2018] [Accepted: 10/30/2018] [Indexed: 01/15/2023]
Abstract
The mitochondrial enzyme ETHE1 is a persulfide dioxygenase essential for cellular sulfide detoxification, and its deficiency causes the severe and complex inherited metabolic disorder ethylmalonic encephalopathy (EE). In spite of well-described clinical symptoms of the disease, detailed cellular and molecular characterization is still ambiguous. Cellular redox regulation has been described to be influenced in ETHE1 deficient cells, and to clarify this further we applied image cytometry and detected decreased levels of reduced glutathione (GSH) in cultivated EE patient fibroblast cells. Cell growth initiation of the EE patient cells was impaired, whereas cell cycle regulation was not. Furthermore, Seahorse metabolic analyzes revealed decreased extracellular acidification, i. e. decreased lactate formation from glycolysis, in the EE patient cells. TMT-based large-scale proteomics was subsequently performed to broadly elucidate cellular consequences of the ETHE1 deficiency. More than 130 proteins were differentially regulated, of which the majority were non-mitochondrial. The proteomics data revealed a link between ETHE1-deficiency and down-regulation of several ribosomal proteins and LIM domain proteins important for cellular maintenance, and up-regulation of cell surface glycoproteins. Furthermore, several proteins of endoplasmic reticulum (ER) were perturbed including proteins influencing disulfide bond formation (e.g. protein disulfide isomerases and peroxiredoxin 4) and calcium-regulated proteins. The results indicate that decreased level of reduced GSH and alterations in proteins of ribosomes, ER and of cell adhesion lie behind the disrupted cell growth of the EE patient cells.
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Affiliation(s)
- Navid Sahebekhtiari
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus N, Denmark
| | - Paula Fernandez-Guerra
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus N, Denmark
| | - Zahra Nochi
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus N, Denmark
| | - Jasper Carlsen
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus N, Denmark
| | - Peter Bross
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus N, Denmark
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus N, Denmark.
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Breining P, Jensen JB, Sundelin EI, Gormsen LC, Jakobsen S, Busk M, Rolighed L, Bross P, Fernandez-Guerra P, Markussen LK, Rasmussen NE, Hansen JB, Pedersen SB, Richelsen B, Jessen N. Metformin targets brown adipose tissue in vivo and reduces oxygen consumption in vitro. Diabetes Obes Metab 2018; 20:2264-2273. [PMID: 29752759 DOI: 10.1111/dom.13362] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 05/01/2018] [Accepted: 05/09/2018] [Indexed: 01/11/2023]
Abstract
AIMS To test the hypothesis that brown adipose tissue (BAT) is a metformin target tissue by investigating in vivo uptake of [11 C]-metformin tracer in mice and studying in vitro effects of metformin on cultured human brown adipocytes. MATERIALS AND METHODS Tissue-specific uptake of metformin was assessed in mice by PET/CT imaging after injection of [11 C]-metformin. Human brown adipose tissue was obtained from elective neck surgery and metformin transporter expression levels in human and murine BAT were determined by qPCR. Oxygen consumption in metformin-treated human brown adipocyte cell models was assessed by Seahorse XF technology. RESULTS Injected [11 C]-metformin showed avid uptake in the murine interscapular BAT depot. Metformin exposure in BAT was similar to hepatic exposure. Non-specific inhibition of the organic cation transporter (OCT) protein by cimetidine administration eliminated BAT exposure to metformin, demonstrating OCT-mediated uptake. Gene expression profiles of OCTs in BAT revealed ample OCT3 expression in both human and mouse BAT. Incubation of a human brown adipocyte cell models with metformin reduced cellular oxygen consumption in a dose-dependent manner. CONCLUSION These results support BAT as a putative metformin target.
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Affiliation(s)
- Peter Breining
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus, Denmark
| | - Jonas B Jensen
- Department of Clinical Medicine, Research Laboratory for Biochemical Pathology, Aarhus University, Aarhus, Denmark
| | - Elias I Sundelin
- Department of Clinical Medicine, Research Laboratory for Biochemical Pathology, Aarhus University, Aarhus, Denmark
| | - Lars C Gormsen
- Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Steen Jakobsen
- Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Morten Busk
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark
| | - Lars Rolighed
- Department of Otorhinolaryngology and Department of Surgery P, Aarhus University Hospital, Aarhus, Denmark
| | - Peter Bross
- Department of Clinical Medicine, Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
| | - Paula Fernandez-Guerra
- Department of Clinical Medicine, Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
| | - Lasse K Markussen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Nanna E Rasmussen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Jacob B Hansen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Steen B Pedersen
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Bjørn Richelsen
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Niels Jessen
- Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Research Laboratory for Biochemical Pathology, Aarhus University, Aarhus, Denmark
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
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12
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Al-Saaidi RA, Rasmussen TB, Birkler RID, Palmfeldt J, Beqqali A, Pinto YM, Nissen PH, Baandrup U, Mølgaard H, Hey TM, Eiskjaer H, Bross P, Mogensen J. The clinical outcome of LMNA missense mutations can be associated with the amount of mutated protein in the nuclear envelope. Eur J Heart Fail 2018; 20:1404-1412. [PMID: 29943882 DOI: 10.1002/ejhf.1241] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [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: 02/06/2018] [Revised: 04/18/2018] [Accepted: 05/21/2018] [Indexed: 12/17/2022] Open
Abstract
AIMS Lamin A/C mutations are generally believed to be associated with a severe prognosis. The aim of this study was to investigate disease expression in three affected families carrying different LMNA missense mutations. Furthermore, the potential molecular disease mechanisms of the mutations were investigated in fibroblasts obtained from mutation carriers. METHODS AND RESULTS A LMNA-p.Arg216Cys missense mutation was identified in a large family with 36 mutation carriers. Disease expression was unusual with a late onset and a favourable prognosis. Two smaller families with severe disease expression were shown to carry a LMNA-p.Arg471Cys and LMNA-p.Arg471His mutation, respectively. LMNA gene and protein expression was investigated in eight different mutation carriers by quantitative reverse transcriptase polymerase chain reaction, Western blotting, immunohistochemistry, and protein mass spectrometry. The results showed that all mutation carriers incorporated mutated lamin protein into the nuclear envelope. Interestingly, the ratio of mutated to wild-type protein was only 30:70 in LMNA-p.Arg216Cys carriers with a favourable prognosis while LMNA-p.Arg471Cys and LMNA-p.Arg471His carriers with a more severe outcome expressed significantly more of the mutated protein by a ratio of 50:50. CONCLUSION The clinical findings indicated that some LMNA mutations may be associated with a favourable prognosis and a low risk of sudden death. Protein expression studies suggested that a severe outcome was associated with the expression of high amounts of mutated protein. These findings may prove to be helpful in counselling and risk assessment of LMNA families.
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Affiliation(s)
- Rasha A Al-Saaidi
- Research Unit for Molecular Medicine, Aarhus University and University Hospital, Aarhus, Denmark
| | | | - Rune I D Birkler
- Research Unit for Molecular Medicine, Aarhus University and University Hospital, Aarhus, Denmark
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Aarhus University and University Hospital, Aarhus, Denmark
| | - Abdelaziz Beqqali
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Yigal M Pinto
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Peter H Nissen
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Ulrik Baandrup
- Centre for Clinical Research, North Denmark Regional Hospital/Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - Henning Mølgaard
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Thomas M Hey
- Department of Cardiology, Odense University Hospital, Odense, Denmark
| | - Hans Eiskjaer
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Peter Bross
- Research Unit for Molecular Medicine, Aarhus University and University Hospital, Aarhus, Denmark
| | - Jens Mogensen
- Department of Cardiology, Odense University Hospital, Odense, Denmark
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13
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Rasmussen T, Al-Saaidi R, Birkler R, Palmfeldt J, Beqqali A, Pinto Y, Baandrup U, Moelgaard H, Hey T, Eiskjaer H, Bross P, Mogensen J. P1607Lamin A/C missense mutations causing cardiomyopathy are associated with highly variable outcomes despite uniform disease mechanisms. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx502.p1607] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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14
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Zhou Y, Al-Saaidi RA, Fernandez-Guerra P, Freude KK, Olsen RKJ, Jensen UB, Gregersen N, Hyttel P, Bolund L, Aagaard L, Bross P, Luo Y. Mitochondrial Spare Respiratory Capacity Is Negatively Correlated with Nuclear Reprogramming Efficiency. Stem Cells Dev 2017; 26:166-176. [DOI: 10.1089/scd.2016.0162] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Yan Zhou
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | | | - Paula Fernandez-Guerra
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University, Aarhus N, Denmark
| | - Kristine K. Freude
- Department of Veterinary Clinical and Animal Sciences, Copenhagen University, Frederiksberg C, Denmark
| | | | - Uffe Birk Jensen
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus N, Denmark
| | - Niels Gregersen
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University, Aarhus N, Denmark
| | - Poul Hyttel
- Department of Veterinary Clinical and Animal Sciences, Copenhagen University, Frederiksberg C, Denmark
| | - Lars Bolund
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
- Danish Regenerative Engineering Alliance for Medicine (DREAM), Aarhus University, Aarhus C, Denmark
| | - Lars Aagaard
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Peter Bross
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University, Aarhus N, Denmark
- Danish Regenerative Engineering Alliance for Medicine (DREAM), Aarhus University, Aarhus C, Denmark
| | - Yonglun Luo
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
- Danish Regenerative Engineering Alliance for Medicine (DREAM), Aarhus University, Aarhus C, Denmark
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15
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Bie AS, Fernandez-Guerra P, Birkler RID, Nisemblat S, Pelnena D, Lu X, Deignan JL, Lee H, Dorrani N, Corydon TJ, Palmfeldt J, Bivina L, Azem A, Herman K, Bross P. Effects of a Mutation in the HSPE1 Gene Encoding the Mitochondrial Co-chaperonin HSP10 and Its Potential Association with a Neurological and Developmental Disorder. Front Mol Biosci 2016; 3:65. [PMID: 27774450 PMCID: PMC5053987 DOI: 10.3389/fmolb.2016.00065] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [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: 07/26/2016] [Accepted: 09/21/2016] [Indexed: 11/13/2022] Open
Abstract
We here report molecular investigations of a missense mutation in the HSPE1 gene encoding the HSP10 subunit of the HSP60/ HSP10 chaperonin complex that assists protein folding in the mitochondrial matrix. The mutation was identified in an infant who came to clinical attention due to infantile spasms at 3 months of age. Clinical exome sequencing revealed heterozygosity for a HSPE1 NM_002157.2:c.217C>T de novo mutation causing replacement of leucine with phenylalanine at position 73 of the HSP10 protein. This variation has never been observed in public exome sequencing databases or the literature. To evaluate whether the mutation may be disease-associated we investigated its effects by in vitro and ex vivo studies. Our in vitro studies indicated that the purified mutant protein was functional, yet its thermal stability, spontaneous refolding propensity, and resistance to proteolytic treatment were profoundly impaired. Mass spectrometric analysis of patient fibroblasts revealed barely detectable levels of HSP10-p.Leu73Phe protein resulting in an almost 2-fold decrease of the ratio of HSP10 to HSP60 subunits. Amounts of the mitochondrial superoxide dismutase SOD2, a protein whose folding is known to strongly depend on the HSP60/HSP10 complex, were decreased to approximately 20% in patient fibroblasts in spite of unchanged SOD2 transcript levels. As a likely consequence, mitochondrial superoxide levels were increased about 2-fold. Although, we cannot exclude other causative or contributing factors, our experimental data support the notion that the HSP10-p.Leu73Phe mutation could be the cause or a strong contributing factor for the disorder in the described patient.
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Affiliation(s)
- Anne S Bie
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Paula Fernandez-Guerra
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Rune I D Birkler
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Shahar Nisemblat
- Department of Biochemistry & Molecular Biology, Tel Aviv University Tel Aviv, Israel
| | - Dita Pelnena
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Xinping Lu
- Department of Biochemistry & Molecular Biology, Tel Aviv University Tel Aviv, Israel
| | - Joshua L Deignan
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at University of California, Los Angeles Los Angeles, CA, USA
| | - Hane Lee
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at University of California, Los Angeles Los Angeles, CA, USA
| | - Naghmeh Dorrani
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at University of California, Los AngelesLos Angeles, CA, USA; Department of Pediatrics, David Geffen School of Medicine at University of California, Los AngelesLos Angeles, CA, USA
| | | | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Liga Bivina
- Division of Genomic Medicine, Department of Pediatrics, UC Davis Health System Sacramento, CA, USA
| | - Abdussalam Azem
- Department of Biochemistry & Molecular Biology, Tel Aviv University Tel Aviv, Israel
| | - Kristin Herman
- Division of Genomic Medicine, Department of Pediatrics, UC Davis Health System Sacramento, CA, USA
| | - Peter Bross
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
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16
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Bross P, Fernandez-Guerra P. Disease-Associated Mutations in the HSPD1 Gene Encoding the Large Subunit of the Mitochondrial HSP60/HSP10 Chaperonin Complex. Front Mol Biosci 2016; 3:49. [PMID: 27630992 PMCID: PMC5006179 DOI: 10.3389/fmolb.2016.00049] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [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: 07/15/2016] [Accepted: 08/22/2016] [Indexed: 01/01/2023] Open
Abstract
Heat shock protein 60 (HSP60) forms together with heat shock protein 10 (HSP10) double-barrel chaperonin complexes that are essential for folding to the native state of proteins in the mitochondrial matrix space. Two extremely rare monogenic disorders have been described that are caused by missense mutations in the HSPD1 gene that encodes the HSP60 subunit of the HSP60/HSP10 chaperonin complex. Investigations of the molecular mechanisms underlying these disorders have revealed that different degrees of reduced HSP60 function produce distinct neurological phenotypes. While mutations with deleterious or strong dominant negative effects are not compatible with life, HSPD1 gene variations found in the human population impair HSP60 function and depending on the mechanism and degree of HSP60 dys- and mal-function cause different phenotypes. We here summarize the knowledge on the effects of disturbances of the function of the HSP60/HSP10 chaperonin complex by disease-associated mutations.
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Affiliation(s)
- Peter Bross
- Research Unit for Molecular Medicine, Department of Molecular Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Paula Fernandez-Guerra
- Research Unit for Molecular Medicine, Department of Molecular Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
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17
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Bross P, Tanguay RM. Mitochondrial Hsp70 and the troubles of nomenclature: leaving behind tradition to gain intuitiveness and clarity. Cell Stress Chaperones 2016; 21:547-51. [PMID: 27211809 PMCID: PMC4908006 DOI: 10.1007/s12192-016-0700-x] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/05/2016] [Indexed: 10/21/2022] Open
Affiliation(s)
- Peter Bross
- Department of Clinical Medicine, Research Unit for Molecular Medicine (MMF), Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus, Denmark.
| | - Robert M Tanguay
- Department of Molecular Biology, Medical Biochemistry and Pathology, Medical School, Lab of Developmental Genetics, IBIS and PROTEO, Université Laval, 1030 avenue de la medicine, Québec, Québec, Canada, G1V 0A6.
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18
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Zhou Y, Liu Y, Hussmann D, Brøgger P, Al-Saaidi RA, Tan S, Lin L, Petersen TS, Zhou GQ, Bross P, Aagaard L, Klein T, Rønn SG, Pedersen HD, Bolund L, Nielsen AL, Sørensen CB, Luo Y. Enhanced genome editing in mammalian cells with a modified dual-fluorescent surrogate system. Cell Mol Life Sci 2016; 73:2543-63. [DOI: 10.1007/s00018-015-2128-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 12/09/2015] [Accepted: 12/29/2015] [Indexed: 12/15/2022]
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19
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Fernandez-Guerra P, Lund M, Corydon TJ, Cornelius N, Gregersen N, Palmfeldt J, Bross P. Application of an Image Cytometry Protocol for Cellular and Mitochondrial Phenotyping on Fibroblasts from Patients with Inherited Disorders. JIMD Rep 2015; 27:17-26. [PMID: 26404456 DOI: 10.1007/8904_2015_494] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 08/13/2015] [Accepted: 08/24/2015] [Indexed: 12/14/2022] Open
Abstract
Cellular phenotyping of human dermal fibroblasts (HDFs) from patients with inherited diseases provides invaluable information for diagnosis, disease aetiology, prognosis and assessing of treatment options. Here we present a cell phenotyping protocol using image cytometry that combines measurements of crucial cellular and mitochondrial parameters: (1) cell number and viability, (2) thiol redox status (TRS), (3) mitochondrial membrane potential (MMP) and (4) mitochondrial superoxide levels (MSLs). With our protocol, cell viability, TRS and MMP can be measured in one small cell sample and MSL on a parallel one. We analysed HDFs from healthy individuals after treatment with various concentrations of hydrogen peroxide (H2O2) for different intervals, to mimic the physiological effects of oxidative stress. Our results show that cell number, viability, TRS and MMP decreased, while MSL increased both in a time- and concentration-dependent manner. To assess the use of our protocol for analysis of HDFs from patients with inherited diseases, we analysed HDFs from two patients with very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency (VLCADD), one with a severe clinical phenotype and one with a mild one. HDFs from both patients displayed increased MSL without H2O2 treatment. Treatment with H2O2 revealed significant differences in MMP and MSL between HDFs from the mild and the severe patient. Our results establish the capacity of our protocol for fast analysis of cellular and mitochondrial parameters by image cytometry in HDFs from patients with inherited metabolic diseases.
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Affiliation(s)
- Paula Fernandez-Guerra
- Department of Clinical Medicine, Research Unit for Molecular Medicine (MMF), Aarhus University Hospital, Brendstrupgaardsvej 100, 8200, Aarhus, Denmark.
| | - M Lund
- Department of Clinical Medicine, Research Unit for Molecular Medicine (MMF), Aarhus University Hospital, Brendstrupgaardsvej 100, 8200, Aarhus, Denmark
| | - T J Corydon
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - N Cornelius
- Department of Clinical Medicine, Research Unit for Molecular Medicine (MMF), Aarhus University Hospital, Brendstrupgaardsvej 100, 8200, Aarhus, Denmark.,Department of clinical Genetics, Applied Human Molecular Genetics, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
| | - N Gregersen
- Department of Clinical Medicine, Research Unit for Molecular Medicine (MMF), Aarhus University Hospital, Brendstrupgaardsvej 100, 8200, Aarhus, Denmark
| | - J Palmfeldt
- Department of Clinical Medicine, Research Unit for Molecular Medicine (MMF), Aarhus University Hospital, Brendstrupgaardsvej 100, 8200, Aarhus, Denmark
| | - Peter Bross
- Department of Clinical Medicine, Research Unit for Molecular Medicine (MMF), Aarhus University Hospital, Brendstrupgaardsvej 100, 8200, Aarhus, Denmark.
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20
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Saunders C, Smith L, Wibrand F, Ravn K, Bross P, Thiffault I, Christensen M, Atherton A, Farrow E, Miller N, Kingsmore SF, Ostergaard E. CLPB variants associated with autosomal-recessive mitochondrial disorder with cataract, neutropenia, epilepsy, and methylglutaconic aciduria. Am J Hum Genet 2015; 96:258-65. [PMID: 25597511 DOI: 10.1016/j.ajhg.2014.12.020] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 12/19/2014] [Indexed: 11/29/2022] Open
Abstract
3-methylglutaconic aciduria (3-MGA-uria) is a nonspecific finding associated with mitochondrial dysfunction, including defects of oxidative phosphorylation. 3-MGA-uria is classified into five groups, of which one, type IV, is genetically heterogeneous. Here we report five children with a form of type IV 3-MGA-uria characterized by cataracts, severe psychomotor regression during febrile episodes, epilepsy, neutropenia with frequent infections, and death in early childhood. Four of the individuals were of Greenlandic descent, and one was North American, of Northern European and Asian descent. Through a combination of homozygosity mapping in the Greenlandic individuals and exome sequencing in the North American, we identified biallelic variants in the caseinolytic peptidase B homolog (CLPB). The causative variants included one missense variant, c.803C>T (p.Thr268Met), and two nonsense variants, c.961A>T (p.Lys321*) and c.1249C>T (p.Arg417*). The level of CLPB protein was markedly decreased in fibroblasts and liver of affected individuals. CLPB is proposed to function as a mitochondrial chaperone involved in disaggregation of misfolded proteins, resulting from stress such as heat denaturation.
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MESH Headings
- Abnormalities, Multiple/genetics
- Abnormalities, Multiple/pathology
- Atrophy/genetics
- Atrophy/pathology
- Base Sequence
- Brain/pathology
- Cataract/genetics
- Cataract/pathology
- Child, Preschool
- Codon, Nonsense/genetics
- Endopeptidase Clp/genetics
- Endopeptidase Clp/metabolism
- Epilepsy/genetics
- Epilepsy/pathology
- Exome/genetics
- Fatal Outcome
- Female
- Fibroblasts/metabolism
- Genes, Recessive/genetics
- Greenland
- Humans
- Infant
- Infant, Newborn
- Liver/metabolism
- Male
- Metabolism, Inborn Errors/genetics
- Metabolism, Inborn Errors/pathology
- Mitochondrial Diseases/genetics
- Mitochondrial Diseases/pathology
- Molecular Sequence Data
- Movement Disorders/genetics
- Movement Disorders/pathology
- Mutation, Missense/genetics
- Neutropenia/genetics
- Neutropenia/pathology
- Sequence Analysis, DNA
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Affiliation(s)
- Carol Saunders
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO 64108, USA; Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, Kansas City, MO 64108, USA.
| | - Laurie Smith
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO 64108, USA; Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108, USA
| | - Flemming Wibrand
- Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Kirstine Ravn
- Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Peter Bross
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Isabelle Thiffault
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO 64108, USA
| | - Mette Christensen
- Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Andrea Atherton
- Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108, USA
| | - Emily Farrow
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO 64108, USA; Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108, USA
| | - Neil Miller
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO 64108, USA
| | - Stephen F Kingsmore
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO 64108, USA; Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, Kansas City, MO 64108, USA; Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO 64108, USA
| | - Elsebet Ostergaard
- Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark.
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21
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Fernández-Guerra P, Birkler RID, Merinero B, Ugarte M, Gregersen N, Rodríguez-Pombo P, Bross P, Palmfeldt J. Selected reaction monitoring as an effective method for reliable quantification of disease-associated proteins in maple syrup urine disease. Mol Genet Genomic Med 2014; 2:383-92. [PMID: 25333063 PMCID: PMC4190873 DOI: 10.1002/mgg3.88] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [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: 03/10/2014] [Revised: 04/25/2014] [Accepted: 04/29/2014] [Indexed: 12/15/2022] Open
Abstract
Selected reaction monitoring (SRM) mass spectrometry can quantitatively measure proteins by specific targeting of peptide sequences, and allows the determination of multiple proteins in one single analysis. Here, we show the feasibility of simultaneous measurements of multiple proteins in mitochondria-enriched samples from cultured fibroblasts from healthy individuals and patients with mutations in branched-chain α-ketoacid dehydrogenase (BCKDH) complex. BCKDH is a mitochondrial multienzyme complex and its defective activity causes maple syrup urine disease (MSUD), a rare but severe inherited metabolic disorder. Four different genes encode the catalytic subunits of BCKDH: E1α (BCKDHA), E1β (BCKDHB), E2 (DBT), and E3 (DLD). All four proteins were successfully quantified in healthy individuals. However, the E1α and E1β proteins were not detected in patients carrying mutations in one of those genes, whereas mRNA levels were almost unaltered, indicating instability of E1α and E1β monomers. Using SRM we elucidated the protein effects of mutations generating premature termination codons or misfolded proteins. SRM is a complement to transcript level measurements and a valuable tool to shed light on molecular mechanisms and on effects of pharmacological therapies at protein level. SRM is particularly effective for inherited disorders caused by multiple proteins such as defects in multienzyme complexes.
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Affiliation(s)
- Paula Fernández-Guerra
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Rune I D Birkler
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Begoña Merinero
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), Centro de Investigación en Red de Enfermedades Raras (CIBERER), IDIPAZ, Universidad Autónoma Madrid Madrid, Spain
| | - Magdalena Ugarte
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), Centro de Investigación en Red de Enfermedades Raras (CIBERER), IDIPAZ, Universidad Autónoma Madrid Madrid, Spain
| | - Niels Gregersen
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Pilar Rodríguez-Pombo
- Dpto Biol. Mol., Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), Centro de Biología Molecular Severo Ochoa, UAM-CSIC, Centro de Investigación en Red de Enfermedades Raras (CIBERER), IDIPAZ, Universidad Autónoma Madrid Madrid, Spain
| | - Peter Bross
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital Aarhus, Denmark
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22
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Rasmussen TB, Nissen PH, Palmfeldt J, Gehmlich K, Dalager S, Jensen UB, Kim WY, Heickendorff L, Mølgaard H, Jensen HK, Baandrup UT, Bross P, Mogensen J. Truncating Plakophilin-2 Mutations in Arrhythmogenic Cardiomyopathy Are Associated With Protein Haploinsufficiency in Both Myocardium and Epidermis. ACTA ACUST UNITED AC 2014; 7:230-40. [DOI: 10.1161/circgenetics.113.000338] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Arrhythmogenic cardiomyopathy (AC) is a hereditary cardiac condition associated with ventricular arrhythmias, heart failure, and sudden death. The disease is most often caused by mutations in the desmosomal gene for plakophilin-2 (
PKP2
), which is expressed in both myocardial and epidermal tissue. This study aimed to investigate protein expression in myocardial tissue of patients with AC carrying
PKP2
mutations and elucidate whether keratinocytes of the same individuals exhibited a similar pattern of protein expression.
Methods and Results—
Direct sequencing of 5 AC genes in 71 unrelated patients with AC identified 10 different
PKP2
mutations in 12 index patients. One patient, heterozygous for a
PKP2
nonsense mutation, developed severe heart failure and underwent cardiac transplantation. Western blotting and immunohistochemistry of the explanted heart showed a significant decrease in PKP2 protein expression without detectable amounts of truncated PKP2 protein. Cultured keratinocytes of the patient showed a similar reduction in PKP2 protein expression. Nine additional
PKP2
mutations were investigated in both cultured keratinocytes and endomyocardial biopsies from affected individuals. It was evident that
PKP2
mutations introducing a premature termination codon in the reading frame were associated with PKP2 transcript and protein levels reduced to ≈50%, whereas a missense variant did not seem to affect the amount of PKP2 protein.
Conclusions—
The results of this study showed that truncating
PKP2
mutations in AC are associated with low expression of the mutant allele and that the myocardial protein expression of PKP2 is mirrored in keratinocytes. These findings indicate that
PKP2
haploinsufficiency contributes to pathogenesis in AC.
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Affiliation(s)
- Torsten B. Rasmussen
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Peter H. Nissen
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Johan Palmfeldt
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Katja Gehmlich
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Søren Dalager
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Uffe B. Jensen
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Won Y. Kim
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Lene Heickendorff
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Henning Mølgaard
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Henrik K. Jensen
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Ulrik T. Baandrup
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Peter Bross
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
| | - Jens Mogensen
- From the Department of Cardiology (T.B.R., W.Y.K., H.M., H.K.J., J.M.), Research Unit for Molecular Medicine (T.B.R., J.P., P.B.), Department of Clinical Biochemistry (P.H.N., L.H.), Institute of Pathology (S.D.), Department of Clinical Genetics (U.B.J.), and MR Centre (W.Y.K.), Aarhus University Hospital, Aarhus, Denmark; Clinical Research Center, Vendsyssel Hospital, Aalborg University, Hjørring, Denmark (U.T.B.); Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of
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23
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Edhager AV, Stenbroen V, Nielsen NS, Bross P, Olsen RKJ, Gregersen N, Palmfeldt J. Proteomic investigation of cultivated fibroblasts from patients with mitochondrial short-chain acyl-CoA dehydrogenase deficiency. Mol Genet Metab 2014; 111:360-368. [PMID: 24485985 DOI: 10.1016/j.ymgme.2014.01.007] [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] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 01/15/2014] [Accepted: 01/15/2014] [Indexed: 12/23/2022]
Abstract
Short-chain acyl-CoA dehydrogenase (SCAD) deficiency is a rare inherited autosomal recessive disorder with not yet well established mechanisms of disease. In the present study, the mitochondrial proteome of five symptomatic patients homozygous for missense variations in the SCAD gene ACADS was investigated in an extensive large-scale proteomic study to map protein perturbations linked to the disease. Fibroblast cultures of patient cells homozygous for either c.319C>T/p.Arg107Cys (n=2) or c.1138C>T/p.Arg380Trp (n=3) in ACADS, and healthy controls (normal human dermal fibroblasts), were studied. The mitochondrial proteome derived from these cultures was analyzed by label free proteomics using high mass accuracy nanoliquid chromatography tandem mass spectrometry (nanoLC-MS/MS). More than 300 mitochondrial proteins were identified and quantified. Thirteen proteins had significant alteration in protein levels in patients carrying variation c.319C>T in ACADS compared to controls and they belonged to various pathways, such as the antioxidant system and amino acid metabolism. Twenty-two proteins were found significantly altered in patients carrying variation c.1138C>T which included proteins associated with fatty acid β-oxidation, amino acid metabolism and protein quality control system. Three proteins were found significantly regulated in both patient groups: adenylate kinase 4 (AK4), nucleoside diphosphate kinase A (NME1) and aldehyde dehydrogenase family 4 member A1 (ALDH4A1). Proteins AK4 and NME1 deserve further investigation because of their involvement in energy reprogramming, cell survival and proliferation with relevance for SCAD deficiency and related metabolic disorders.
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Affiliation(s)
- Anders V Edhager
- Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Vibeke Stenbroen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Nadia Sukusu Nielsen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Peter Bross
- Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Rikke K J Olsen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Niels Gregersen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark.
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24
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Kleinridders A, Lauritzen HPMM, Ussar S, Christensen JH, Mori MA, Bross P, Kahn CR. Leptin regulation of Hsp60 impacts hypothalamic insulin signaling. J Clin Invest 2014; 123:4667-80. [PMID: 24084737 DOI: 10.1172/jci67615] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 08/01/2013] [Indexed: 11/17/2022] Open
Abstract
Type 2 diabetes is characterized by insulin resistance and mitochondrial dysfunction in classical target tissues such as muscle, fat, and liver. Using a murine model of type 2 diabetes, we show that there is hypothalamic insulin resistance and mitochondrial dysfunction due to downregulation of the mitochondrial chaperone HSP60. HSP60 reduction in obese, diabetic mice was due to a lack of proper leptin signaling and was restored by leptin treatment. Knockdown of Hsp60 in a mouse hypothalamic cell line mimicked the mitochondrial dysfunction observed in diabetic mice and resulted in increased ROS production and insulin resistance, a phenotype that was reversed with antioxidant treatment. Mice with a heterozygous deletion of Hsp60 exhibited mitochondrial dysfunction and hypothalamic insulin resistance. Targeted acute downregulation of Hsp60 in the hypothalamus also induced insulin resistance, indicating that mitochondrial dysfunction can cause insulin resistance in the hypothalamus. Importantly, type 2 diabetic patients exhibited decreased expression of HSP60 in the brain, indicating that this mechanism is relevant to human disease. These data indicate that leptin plays an important role in mitochondrial function and insulin sensitivity in the hypothalamus by regulating HSP60. Moreover, leptin/insulin crosstalk in the hypothalamus impacts energy homeostasis in obesity and insulin-resistant states.
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25
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Magnoni R, Palmfeldt J, Hansen J, Christensen JH, Corydon TJ, Bross P. The Hsp60 folding machinery is crucial for manganese superoxide dismutase folding and function. Free Radic Res 2013; 48:168-79. [DOI: 10.3109/10715762.2013.858147] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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26
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Al-Saaidi R, Rasmussen TB, Palmfeldt J, Nissen PH, Beqqali A, Hansen J, Pinto YM, Boesen T, Mogensen J, Bross P. The LMNA mutation p.Arg321Ter associated with dilated cardiomyopathy leads to reduced expression and a skewed ratio of lamin A and lamin C proteins. Exp Cell Res 2013; 319:3010-9. [PMID: 24001739 DOI: 10.1016/j.yexcr.2013.08.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 07/31/2013] [Accepted: 08/19/2013] [Indexed: 11/19/2022]
Abstract
Dilated cardiomyopathy (DCM) is a disease of the heart muscle characterized by cardiac chamber enlargement and reduced systolic function of the left ventricle. Mutations in the LMNA gene represent the most frequent known genetic cause of DCM associated with disease of the conduction systems. The LMNA gene generates two major transcripts encoding the nuclear lamina major components lamin A and lamin C by alternative splicing. Both haploinsuffiency and dominant negative effects have been proposed as disease mechanism for premature termination codon (PTC) mutations in LMNA. These mechanisms however are still not clearly established. In this study, we used a representative LMNA nonsense mutation, p.Arg321Ter, to shed light on the molecular disease mechanisms. Cultured fibroblasts from three DCM patients carrying this mutation were analyzed. Quantitative reverse transcriptase PCR and sequencing of these PCR products indicated that transcripts from the mutant allele were degraded by the nonsense-mediated mRNA decay (NMD) mechanism. The fact that no truncated mutant protein was detectable in western blot (WB) analysis strengthens the notion that the mutant transcript is efficiently degraded. Furthermore, WB analysis showed that the expression of lamin C protein was reduced by the expected approximately 50%. Clearly decreased lamin A and lamin C levels were also observed by immunofluorescence microscopy analysis. However, results from both WB and nano-liquid chromatography/mass spectrometry demonstrated that the levels of lamin A protein were more reduced suggesting an effect on expression of lamin A from the wild type allele. PCR analysis of the ratio of lamin A to lamin C transcripts showed unchanged relative amounts of lamin A transcript suggesting that the effect on the wild type allele was operative at the protein level. Immunofluorescence microscopy analysis showed no abnormal nuclear morphology of patient fibroblast cells. Based on these data, we propose that heterozygosity for the nonsense mutation causes NMD degradation of the mutant transcripts blocking expression of the truncated mutant protein and an additional trans effect on lamin A protein levels expressed from the wild type allele. We discuss the possibility that skewing of the lamin A to lamin C ratio may contribute to ensuing processes that destabilize cardiomyocytes and trigger cardiomyopathy.
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Affiliation(s)
- Rasha Al-Saaidi
- Research Unit for Molecular Medicine, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
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27
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Rasmussen TB, Palmfeldt J, Nissen PH, Magnoni R, Dalager S, Jensen UB, Kim WY, Heickendorff L, Mølgaard H, Jensen HK, Baandrup UT, Bross P, Mogensen J. Mutated desmoglein-2 proteins are incorporated into desmosomes and exhibit dominant-negative effects in arrhythmogenic right ventricular cardiomyopathy. Hum Mutat 2013; 34:697-705. [PMID: 23381804 DOI: 10.1002/humu.22289] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 01/28/2013] [Indexed: 01/29/2023]
Abstract
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a hereditary cardiac condition associated with ventricular arrhythmias, heart failure, and sudden death. The most frequent ARVC genes encode desmosomal proteins of which mutations in desmoglein-2 (DSG2), account for 10%-20% of cases. This study aimed to investigate how DSG2 mutations contribute to the pathogenesis of ARVC. Initial mutation analysis of DSG2 in 71 probands identified the first family reported with recessively inherited ARVC due to a missense mutation. In addition, three recognized DSG2 mutations were identified in 12 families. These results and further mutation analyses of four additional desmosomal genes indicated that ARVC caused by DSG2 mutations is often transmitted by recessive or digenic inheritance. Because desmosomal proteins are also expressed in skin tissue, keratinocytes served as a cell model to investigate DSG2 protein expression by Western blotting, 2D-PAGE, and liquid chromatography-mass spectrometry. The results showed that heterozygous mutation carriers expressed both mutated and wild-type DSG2 proteins. These findings were consistent with the results obtained by immunohistochemistry of endomyocardial biopsies and epidermal tissue of mutation carriers, which indicated a normal cellular distribution of DSG2. The results suggested a dominant-negative effect of the mutated DSG2 proteins because they were incorporated into the desmosomes.
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28
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Magnoni R, Palmfeldt J, Christensen JH, Sand M, Maltecca F, Corydon TJ, West M, Casari G, Bross P. Late onset motoneuron disorder caused by mitochondrial Hsp60 chaperone deficiency in mice. Neurobiol Dis 2013; 54:12-23. [PMID: 23466696 DOI: 10.1016/j.nbd.2013.02.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 01/29/2013] [Accepted: 02/22/2013] [Indexed: 01/07/2023] Open
Abstract
Cells rely on efficient protein quality control systems (PQCs) to maintain proper activity of mitochondrial proteins. As part of this system, the mitochondrial chaperone Hsp60 assists folding of matrix proteins and it is an essential protein in all organisms. Mutations in Hspd1, the gene encoding Hsp60, are associated with two human inherited diseases of the nervous system, a dominantly inherited form of spastic paraplegia (SPG13) and an autosomal recessively inherited white matter disorder termed MitCHAP60 disease. Although the connection between mitochondrial failure and neurodegeneration is well known in many neurodegenerative disorders, such as Huntington's disease, Parkinson's disease, and hereditary spastic paraplegia, the molecular basis of the neurodegeneration associated with these diseases is still ill-defined. Here, we investigate mice heterozygous for a knockout allele of the Hspd1 gene encoding Hsp60. Our results demonstrate that Hspd1 haploinsufficiency is sufficient to cause a late onset and slowly progressive deficit in motor functions in mice. We furthermore emphasize the crucial role of the Hsp60 chaperone in mitochondrial function by showing that the motor phenotype is associated with morphological changes of mitochondria, deficient ATP synthesis, and in particular, a defect in the assembly of the respiratory chain complex III in neuronal tissues. In the current study, we propose that our heterozygous Hsp60 mouse model is a valuable model system for the investigation of the link between mitochondrial dysfunction and neurodegeneration.
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Affiliation(s)
- Raffaella Magnoni
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Health Aarhus University Hospital and Aarhus University, Aarhus, Denmark.
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Bross P, Magnoni R, Sigaard Bie A. Molecular Chaperone Disorders: Defective Hsp60 in Neurodegeneration. Curr Top Med Chem 2013; 12:2491-503. [DOI: 10.2174/1568026611212220005] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 08/23/2012] [Accepted: 08/23/2012] [Indexed: 11/22/2022]
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Bross P, Magnoni R, Sigaard Bie A. Molecular Chaperone Disorders: Defective Hsp60 in Neurodegeneration. Curr Top Med Chem 2013. [DOI: 10.2174/15680266112129990071] [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: 11/22/2022]
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Parnas A, Nisemblat S, Weiss C, Levy-Rimler G, Pri-Or A, Zor T, Lund PA, Bross P, Azem A. Identification of elements that dictate the specificity of mitochondrial Hsp60 for its co-chaperonin. PLoS One 2012; 7:e50318. [PMID: 23226518 PMCID: PMC3514286 DOI: 10.1371/journal.pone.0050318] [Citation(s) in RCA: 30] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Accepted: 10/18/2012] [Indexed: 01/28/2023] Open
Abstract
Type I chaperonins (cpn60/Hsp60) are essential proteins that mediate the folding of proteins in bacteria, chloroplast and mitochondria. Despite the high sequence homology among chaperonins, the mitochondrial chaperonin system has developed unique properties that distinguish it from the widely-studied bacterial system (GroEL and GroES). The most relevant difference to this study is that mitochondrial chaperonins are able to refold denatured proteins only with the assistance of the mitochondrial co-chaperonin. This is in contrast to the bacterial chaperonin, which is able to function with the help of co-chaperonin from any source. The goal of our work was to determine structural elements that govern the specificity between chaperonin and co-chaperonin pairs using mitochondrial Hsp60 as model system. We used a mutagenesis approach to obtain human mitochondrial Hsp60 mutants that are able to function with the bacterial co-chaperonin, GroES. We isolated two mutants, a single mutant (E321K) and a double mutant (R264K/E358K) that, together with GroES, were able to rescue an E. coli strain, in which the endogenous chaperonin system was silenced. Although the mutations are located in the apical domain of the chaperonin, where the interaction with co-chaperonin takes place, none of the residues are located in positions that are directly responsible for co-chaperonin binding. Moreover, while both mutants were able to function with GroES, they showed distinct functional and structural properties. Our results indicate that the phenotype of the E321K mutant is caused mainly by a profound increase in the binding affinity to all co-chaperonins, while the phenotype of R264K/E358K is caused by a slight increase in affinity toward co-chaperonins that is accompanied by an alteration in the allosteric signal transmitted upon nucleotide binding. The latter changes lead to a great increase in affinity for GroES, with only a minor increase in affinity toward the mammalian mitochondrial co-chaperonin.
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Affiliation(s)
- Avital Parnas
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Shahar Nisemblat
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Celeste Weiss
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Galit Levy-Rimler
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Amir Pri-Or
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Tsaffrir Zor
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Peter A. Lund
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - Peter Bross
- Research Unit for Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Abdussalam Azem
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
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Rasmussen TB, Hansen J, Nissen PH, Palmfeldt J, Dalager S, Jensen UB, Kim WY, Heickendorff L, Mølgaard H, Jensen HK, Sørensen KE, Baandrup UT, Bross P, Mogensen J. Protein expression studies of desmoplakin mutations in cardiomyopathy patients reveal different molecular disease mechanisms. Clin Genet 2012; 84:20-30. [PMID: 23137101 DOI: 10.1111/cge.12056] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 11/06/2012] [Accepted: 06/11/2012] [Indexed: 11/29/2022]
Abstract
Mutations in the gene for desmoplakin (DSP) may cause arrhythmogenic right ventricular cardiomyopathy (ARVC) and Carvajal syndrome (CS). Desmoplakin is part of all desmosomes, which are abundantly expressed in both myocardial and epidermal tissue and serve as intercellular mechanical junctions. This study aimed to investigate protein expression in myocardial and epidermal tissue of ARVC and CS patients carrying DSP mutations in order to elucidate potential molecular disease mechanisms. Genetic investigations identified three ARVC patients carrying different heterozygous DSP mutations in addition to a homozygous DSP mutation in a CS patient. The protein expression of DSP in mutation carriers was evaluated in biopsies from myocardial and epidermal tissue by immunohistochemistry. Keratinocyte cultures were established from skin biopsies of mutation carriers and characterized by reverse transcriptase polymerase chain reaction, western blotting, and protein mass spectrometry. The results showed that the mutation carriers had abnormal DSP expression in both myocardial and epidermal tissue. The investigations revealed that the disease mechanisms varied accordingly to the specific types of DSP mutation identified and included haploinsufficiency, dominant-negative effects, or a combination hereof. Furthermore, the results suggest that the keratinocytes cultured from patients are a valuable and easily accessible resource to elucidate the effects of desmosomal gene mutations in humans.
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Affiliation(s)
- T B Rasmussen
- Department of Cardiology; Research Unit for Molecular Medicine, Odense University Hospital, Sdr. Boulevard 29, Odense C, Denmark
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Bross P, Frederiksen JB, Bie AS, Hansen J, Palmfeldt J, Nielsen MN, Duno M, Lund AM, Christensen E. Heterozygosity for an in-frame deletion causes glutaryl-CoA dehydrogenase deficiency in a patient detected by newborn screening: investigation of the effect of the mutant allele. J Inherit Metab Dis 2012; 35:787-96. [PMID: 22231382 DOI: 10.1007/s10545-011-9437-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 10/31/2011] [Accepted: 12/08/2011] [Indexed: 11/30/2022]
Abstract
A patient with suspected glutaric aciduria type 1 (GA-1) was detected by newborn screening. GA-1 is known as an autosomal recessively inherited disease due to defects in the gene coding for glutaryl-CoA dehydrogenase (GCDH), a mitochondrial enzyme involved in the catabolism of the amino acids hydroxylysine, lysine and tryptophan. DNA and cDNA sequencing revealed a 18 bp deletion (c.553_570del18) resulting in deletion of six amino acids (p.Gly185_Ser190del) in one allele and no sequence changes in the other allele. Confirmatory biochemical analysis of blood, urine and cultured fibroblasts from the proband were consistent with a mild biochemical GA-1 phenotype. Recombinant expression of the mutant variant in E. coli showed that the GCDH-(p.Gly185_Ser190del) protein displayed severely decreased assembly into tetramers and enzyme activity. To discover a potential dominant negative effect of the mutant protein, we engineered a prokaryotic expression system in which expression of a wild type and a mutant GCDH allele is controlled by separately inducible promoters. These cells displayed decreased levels of GCDH tetramer and enzyme activity when expressing both the wild type and the mutant GCDH variant protein compared to the situation when only the wild type allele was expressed. Further experiments suggest that the major impact of the GCDH-(p.Gly185_Ser190del) protein in heterozygous cells consists of hampering the assembly of wild type GCDH into tetramers. Our experimental data are consistent with the hypothesis that heterozygosity for this mutation confers a dominant negative effect resulting in a GCDH enzyme activity that is significantly lower than the expected 50%.
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Affiliation(s)
- Peter Bross
- Research Unit for Molecular Medicine, Aarhus University Hospital and Aarhus University, Institute of Clinical Medicine, Aarhus, Denmark.
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Andresen BS, Lund AM, Hougaard DM, Christensen E, Gahrn B, Christensen M, Bross P, Vested A, Simonsen H, Skogstrand K, Olpin S, Brandt NJ, Skovby F, Nørgaard-Pedersen B, Gregersen N. MCAD deficiency in Denmark. Mol Genet Metab 2012; 106:175-88. [PMID: 22542437 DOI: 10.1016/j.ymgme.2012.03.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 03/24/2012] [Accepted: 03/24/2012] [Indexed: 11/18/2022]
Abstract
Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is the most common defect of fatty acid oxidation. Many countries have introduced newborn screening for MCADD, because characteristic acylcarnitines can easily be identified in filter paper blood spot samples by tandem mass spectrometry (MS/MS), because MCADD is a frequent disease, and because of the success of early treatment initiated before clinical symptoms have emerged. In Denmark we have screened 519,350 newborns for MCADD by MS/MS and identified 58 affected babies. The diagnosis of MCADD was confirmed in all 58 newborns by mutation analysis. This gives an incidence of MCADD detected by newborn screening in Denmark of 1/8954. In sharp contrast to this we found that the incidence of clinically presenting MCADD in Denmark in the 10 year period preceding introduction of MS/MS-based screening was only 1 in 39,691. This means that four times more newborns with MCADD are detected by screening than what is expected based on the number of children presenting clinically in an unscreened population. The mutation spectrum in the newborns detected by screening is different from that observed in clinically presenting patients with a much lower proportion of newborns being homozygous for the prevalent disease-causing c.985A>G mutation. A significant number of the newborns have genotypes with mutations that have not been observed in patients detected clinically. Some of these mutations, like c.199T>C and c.127G>A, are always associated with a milder biochemical phenotype and may cause a milder form of MCADD with a relatively low risk of disease manifestation, thereby explaining part of the discrepancy between the frequency of clinically manifested MCADD and the frequency of MCADD determined by screening. In addition, our data suggest that some of this discrepancy can be explained by a reduced penetrance of the c.985A>G mutation, with perhaps only 50% of c.985A>G homozygotes presenting with disease manifestations. Interestingly, we also report that the observed number of newborns identified by screening who are homozygous for the c.985A>G mutation is twice that predicted from the estimated carrier frequency. We therefore redetermined the carrier frequency in a new sample of 1946 blood spots using a new assay, but this only confirmed that the c.985A>G carrier frequency in Denmark is approximately 1/105. We conclude that MCADD is much more frequent than expected, has a reduced penetrance and that rapid genotyping using the initial blood spot sample is important for correct diagnosis and counseling.
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Affiliation(s)
- Brage Storstein Andresen
- Research Unit for Molecular Medicine, Aarhus University Hospital and Faculty of Health Science, Skejby Sygehus, Aarhus, Denmark.
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Cornelius N, Frerman FE, Corydon TJ, Palmfeldt J, Bross P, Gregersen N, Olsen RKJ. Molecular mechanisms of riboflavin responsiveness in patients with ETF-QO variations and multiple acyl-CoA dehydrogenation deficiency. Hum Mol Genet 2012; 21:3435-48. [PMID: 22611163 DOI: 10.1093/hmg/dds175] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Riboflavin-responsive forms of multiple acyl-CoA dehydrogenation deficiency (RR-MADD) have been known for years, but with presumed defects in the formation of the flavin adenine dinucleotide (FAD) co-factor rather than genetic defects of electron transfer flavoprotein (ETF) or electron transfer flavoprotein-ubiquinone oxidoreductase (ETF-QO). It was only recently established that a number of RR-MADD patients carry genetic defects in ETF-QO and that the well-documented clinical efficacy of riboflavin treatment may be based on a chaperone effect that can compensate for inherited folding defects of ETF-QO. In the present study, we investigate the molecular mechanisms and the genotype-phenotype relationships for the riboflavin responsiveness in MADD, using a human HEK-293 cell expression system. We studied the influence of riboflavin and temperature on the steady-state level and the activity of variant ETF-QO proteins identified in patients with RR-MADD, or non- and partially responsive MADD. Our results showed that variant ETF-QO proteins associated with non- and partially responsive MADD caused severe misfolding of ETF-QO variant proteins when cultured in media with supplemented concentrations of riboflavin. In contrast, variant ETF-QO proteins associated with RR-MADD caused milder folding defects when cultured at the same conditions. Decreased thermal stability of the variants showed that FAD does not completely correct the structural defects induced by the variation. This may cause leakage of electrons and increased reactive oxygen species, as reflected by increased amounts of cellular peroxide production in HEK-293 cells expressing the variant ETF-QO proteins. Finally, we found indications of prolonged association of variant ETF-QO protein with the Hsp60 chaperonin in the mitochondrial matrix, supporting indications of folding defects in the variant ETF-QO proteins.
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Affiliation(s)
- Nanna Cornelius
- The Research Unit for Molecular Medicine, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University, Denmark.
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36
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Bie AS, Palmfeldt J, Hansen J, Christensen R, Gregersen N, Corydon TJ, Bross P. A cell model to study different degrees of Hsp60 deficiency in HEK293 cells. Cell Stress Chaperones 2011; 16:633-40. [PMID: 21717087 PMCID: PMC3220388 DOI: 10.1007/s12192-011-0275-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 06/10/2011] [Accepted: 06/10/2011] [Indexed: 12/19/2022] Open
Abstract
Mitochondrial dysfunction is associated with neurodegenerative diseases and mutations in the HSPD1 gene, encoding the mitochondrial Hsp60 chaperone, are the causative factors of two neurodegenerative diseases, hereditary spastic paraplegia and MitChap60 disease. In cooperation with Hsp10, Hsp60 forms a barrel-shaped complex, which encloses unfolded polypeptides and provides an environment facilitating folding. We have generated an Hsp60 variant with a mutation (Asp423Ala) in the ATPase domain and established a stable human embryonic kidney (HEK293) cell line allowing tetracycline-controlled expression of this mutant variant. We monitored expression of the Hsp60-Asp423Ala variant protein following induction and examined its effects on cellular properties. We showed that the folding of mitochondrial-targeted green fluorescent protein, a well-known substrate protein of Hsp60, was consistently impaired in cells expressing Hsp60-Asp423Ala. The level of the Hsp60-Asp423Ala variant protein increased over time upon induction, cell proliferation stopped after 48-h induction and mitochondrial membrane potential decreased in a time-dependent manner. In summary, we have established a stable cell line with controllable expression of an Hsp60 variant, which allows detailed studies of different degrees of Hsp60 deficiency.
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Affiliation(s)
- Anne Sigaard Bie
- Research Unit for Molecular Medicine (MMF), Aarhus University Hospital, Skejby, Aarhus N, Denmark.
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Hansen J, Palmfeldt J, Vang S, Corydon TJ, Gregersen N, Bross P. Quantitative proteomics reveals cellular targets of celastrol. PLoS One 2011; 6:e26634. [PMID: 22046318 PMCID: PMC3202559 DOI: 10.1371/journal.pone.0026634] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 09/30/2011] [Indexed: 12/29/2022] Open
Abstract
Celastrol, a natural substance isolated from plant extracts used in traditional Chinese medicine, has been extensively investigated as a possible drug for treatment of cancer, autoimmune diseases, and protein misfolding disorders. Although studies focusing on celastrol's effects in specific cellular pathways have revealed a considerable number of targets in a diverse array of in vitro models there is an essential need for investigations that can provide a global view of its effects. To assess cellular effects of celastrol and to identify target proteins as biomarkers for monitoring treatment regimes, we performed large-scale quantitative proteomics in cultured human lymphoblastoid cells, a cell type that can be readily prepared from human blood samples. Celastrol substantially modified the proteome composition and 158 of the close to 1800 proteins with robust quantitation showed at least a 1.5 fold change in protein levels. Up-regulated proteins play key roles in cytoprotection with a prominent group involved in quality control and processing of proteins traversing the endoplasmic reticulum. Increased levels of proteins essential for the cellular protection against oxidative stress including heme oxygenase 1, several peroxiredoxins and thioredoxins as well as proteins involved in the control of iron homeostasis were also observed. Specific analysis of the mitochondrial proteome strongly indicated that the mitochondrial association of certain antioxidant defense and apoptosis-regulating proteins increased in cells exposed to celastrol. Analysis of selected mRNA transcripts showed that celastrol activated several different stress response pathways and dose response studies furthermore showed that continuous exposure to sub-micromolar concentrations of celastrol is associated with reduced cellular viability and proliferation. The extensive catalog of regulated proteins presented here identifies numerous cellular effects of celastrol and constitutes a valuable biomarker tool for the development and monitoration of disease treatment strategies.
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Affiliation(s)
- Jakob Hansen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Skejby, Aarhus, Denmark.
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Lucas TG, Henriques BJ, Rodrigues JV, Bross P, Gregersen N, Gomes CM. Cofactors and metabolites as potential stabilizers of mitochondrial acyl-CoA dehydrogenases. Biochim Biophys Acta Mol Basis Dis 2011; 1812:1658-63. [PMID: 21968293 DOI: 10.1016/j.bbadis.2011.09.009] [Citation(s) in RCA: 34] [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: 07/15/2011] [Revised: 09/14/2011] [Accepted: 09/15/2011] [Indexed: 12/31/2022]
Abstract
Protein misfolding is a hallmark of a number of metabolic diseases, in which fatty acid oxidation defects are included. The latter result from genetic deficiencies in transport proteins and enzymes of the mitochondrial β-oxidation, and milder disease conditions frequently result from conformational destabilization and decreased enzymatic function of the affected proteins. Small molecules which have the ability to raise the functional levels of the affected protein above a certain disease threshold are thus valuable tools for effective drug design. In this work we have investigated the effect of mitochondrial cofactors and metabolites as potential stabilizers in two β-oxidation acyl-CoA dehydrogenases: short chain acyl-CoA dehydrogenase and the medium chain acyl-CoA dehydrogenase as well as glutaryl-CoA dehydrogenase, which is involved in lysine and tryptophan metabolism. We found that near physiological concentrations (low micromolar) of FAD resulted in a spectacular enhancement of the thermal stabilities of these enzymes and prevented enzymatic activity loss during a 1h incubation at 40°C. A clear effect of the respective substrate, which was additive to that of the FAD effect, was also observed for short- and medium-chain acyl-CoA dehydrogenase but not for glutaryl-CoA dehydrogenase. In conclusion, riboflavin may be beneficial during feverish crises in patients with short- and medium-chain acyl-CoA dehydrogenase as well as in glutaryl-CoA dehydrogenase deficiencies, and treatment with substrate analogs to butyryl- and octanoyl-CoAs could theoretically enhance enzyme activity for some enzyme proteins with inherited folding difficulties.
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Affiliation(s)
- Tânia G Lucas
- Instituto Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
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Henriques BJ, Olsen RK, Bross P, Gomes CM. Emerging roles for riboflavin in functional rescue of mitochondrial β-oxidation flavoenzymes. Curr Med Chem 2011; 17:3842-54. [PMID: 20858216 DOI: 10.2174/092986710793205462] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 09/15/2010] [Indexed: 11/22/2022]
Abstract
Riboflavin, commonly known as vitamin B2, is the precursor of flavin cofactors. It is present in our typical diet, and inside the cells it is metabolized to FMN and FAD. As a result of their rather unique and flexible chemical properties these flavins are among the most important redox cofactors present in a large series of different enzymes. A problem in riboflavin metabolism or a low intake of this vitamin will have consequences on the level of FAD and FMN in the cell, resulting in disorders associated with riboflavin deficiency. In a few number of cases, riboflavin deficiency is associated with impaired oxidative folding, cell damage and impaired heme biosynthesis. More relevant are several studies referring reduced activity of enzymes such as dehydrogenases involved in oxidative reactions, respiratory complexes and enzymes from the fatty acid β-oxidation pathway. The role of this vitamin in mitochondrial metabolism, and in particular in fatty acid oxidation, will be discussed in this review. The basic aspects concerning riboflavin and flavin metabolism and deficiency will be addressed, as well as an overview of the role of the different flavoenzymes and flavin chemistry in fatty acid β-oxidation, merging clinical, cellular and biochemical perspectives. A number of recent studies shedding new light on the cellular processes and biological effects of riboflavin supplementation in metabolic disease will also be overviewed. Overall, a deeper understanding of these emerging roles of riboflavin intake is essential to design better therapies.
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Affiliation(s)
- Bárbara J Henriques
- Instituto Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
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40
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Abstract
Cell survival and death are complex matters. Too much survival may lead to cancer and too much cell death may result in tissue degeneration. In this chapter, we will first of all focus on the cellular survival mechanisms that promote correct folding and maintenance of protein function. These mechanisms include protein quality control (PQC) systems comprising molecular chaperones and intracellular proteases in the cytosol, endoplasmatic reticulum (ER) and in the mitochondria. In addition to the PQC systems, mechanisms elicited by misfolded proteins, known as unfolded protein responses (UPRs), including induction/activation of antioxidant systems are also present in the three compartments of the cell. Second, we will discuss the mechanisms by which misfolded proteins lead to the generation of oxidative stress in the form of reactive oxygen species (ROS) and reactive nitrogen species (RNS). These species are produced mainly from superoxide (O2-) generated in the mitochondrial respiratory chain and from nitrogen oxide (NO) produced by the mitochondrial nitrogen oxide synthetase (mtNOS). Third, the effects of oxidative stress will be discussed, both with respect to mitochondrial dynamics, i.e., fission and fusion, and the related elimination of dysfunctional mitochondria by cellular cleaning systems, i.e., mitophagy or mitoptosis, and related to the generation and cellular effects of oxidatively modified proteins, which closes a vicious cycle of protein misfolding and oxidative stress.
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Christensen JH, Nielsen MN, Hansen J, Füchtbauer A, Füchtbauer EM, West M, Corydon TJ, Gregersen N, Bross P. Inactivation of the hereditary spastic paraplegia-associated Hspd1 gene encoding the Hsp60 chaperone results in early embryonic lethality in mice. Cell Stress Chaperones 2010; 15:851-63. [PMID: 20393889 PMCID: PMC3024079 DOI: 10.1007/s12192-010-0194-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 03/19/2010] [Accepted: 03/23/2010] [Indexed: 12/16/2022] Open
Abstract
The mitochondrial Hsp60 chaperonin plays an important role in sustaining cellular viability. Its dysfunction is related to inherited forms of the human diseases spastic paraplegia and hypomyelinating leukodystrophy. However, it is unknown whether the requirement for Hsp60 is neuron specific or whether a complete loss of the protein will impair mammalian development and postnatal survival. In this study, we describe the generation and characterization of a mutant mouse line bearing an inactivating gene-trap insertion in the Hspd1 gene encoding Hsp60. We found that heterozygous mice were born at the expected ratio compared to wild-type mice and displayed no obvious phenotype deficits. Using quantitative reverse transcription PCR, we found significantly decreased levels of the Hspd1 transcript in all of the tissues examined, demonstrating that the inactivation of the Hspd1 gene is efficient. By Western blot analysis, we found that the amount of Hsp60 protein, compared to either cytosolic tubulin or mitochondrial voltage-dependent anion-selective channel protein 1/porin, was decreased as well. The expression of the nearby Hspe1 gene, which encodes the Hsp10 co-chaperonin, was concomitantly down regulated in the liver, and the protein levels in all tissues except the brain were reduced. Homozygous Hspd1 mutant embryos, however, died shortly after implantation (day 6.5 to 7.5 of gestation, Theiler stages 9–10). Our results demonstrate that Hspd1 is an essential gene for early embryonic development in mice, while reducing the amount of Hsp60 by inactivation of one allele of the gene is compatible with survival to term as well as postnatal life.
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Affiliation(s)
- Jane H Christensen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Skejby, Denmark.
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42
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Singh R, Kølvraa S, Bross P, Christensen K, Bathum L, Gregersen N, Tan Q, Rattan SIS. Anti-inflammatory heat shock protein 70 genes are positively associated with human survival. Curr Pharm Des 2010; 16:796-801. [PMID: 20388090 DOI: 10.2174/138161210790883499] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Accepted: 10/18/2009] [Indexed: 12/31/2022]
Abstract
A positive relationship between stress tolerance and longevity has been observed in several model systems. That the same correlation is applicable in humans and that it may be open to experimental manipulation for extending human lifespan requires studies on association of stress genes with longevity. The involvement of heat shock protein 70 (Hsp70) in cellular maintenance and repair mechanisms, including its role as an anti-inflammatory protein, makes it a suitable candidate for studying such associations. We have studied the association of three single nucleotide polymorphisms, HSPA1A (-110A>C), HSPA1B (1267A>G), and HSPA1L (2437T>C), present in the three HSP70 genes, with human survival, in a cohort of individuals born in the year 1905. This population cohort is a part of the longitudinal study of Danish nonagenarians. Since DNA samples were already collected in 1998, this gave us the opportunity to perform survival analysis on these subjects. Haplotype relative risk, and genotype relative risk were calculated to measure the effects of haplotypes and genotypes on human survival in a sex-specific manner. A significant association of HSPA1A-AA (RR=3.864; p=0.016) and HSPA1B-AA (RR=2.764; p=0.039) genotypes with poor survival was observed in female subjects. Also the female carriers of haplotype G-C-T had longer survival than the non-carriers (HRR=0.550; p=0.015). On an average, female carriers of the G-C-T haplotype live about one year longer than non-carriers. This result corroborates our previous observations from heat shock response (HSR) study where we had shown that after heat stimulation, mononuclear cells from the carriers of genotype HSPA1L-TT had better HSR than cells with the HSPA1L-CC genotype.
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Henriques BJ, Bross P, Gomes CM. Mutational hotspots in electron transfer flavoprotein underlie defective folding and function in multiple acyl-CoA dehydrogenase deficiency. Biochim Biophys Acta Mol Basis Dis 2010; 1802:1070-7. [PMID: 20674745 DOI: 10.1016/j.bbadis.2010.07.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 07/13/2010] [Accepted: 07/16/2010] [Indexed: 10/19/2022]
Abstract
We have carried out an extensive in silico analysis on 18 disease associated missense mutations found in electron transfer flavoprotein (ETF), and found that mutations fall essentially in two groups, one in which mutations affect protein folding and assembly, and another one in which mutations impair catalytic activity and disrupt interactions with partner dehydrogenases. We have further experimentally analyzed three of these mutations, ETFβ-p.Cys42Arg, ETFβ-p.Asp128Asn and ETFβ-p.Arg191Cys, which have been found in homozygous form in patients and which typify different scenarios in respect to the clinical phenotypes. The ETFβ-p.Cys42Arg mutation, related to a severe form of multiple acyl-CoA dehydrogenase deficiency (MADD), affects directly the AMP binding site and intersubunit contacts and impairs correct protein folding. The two other variations, ETFβ-p.Asp128Asn and ETFβ-p.Arg191Cys, are both associated with mild MADD, but these mutations have a different impact on ETF. Although none affects the overall α/β fold topology as shown by far-UV CD, analysis of the purified proteins shows that both have substantially decreased enzymatic activity and conformational stability. Altogether, this study combines in silico analysis of mutations with experimental data and has allowed establishing structural hotspots within the ETF fold that are useful to provide a rationale for the prediction of effects of mutations in ETF.
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Affiliation(s)
- Bárbara J Henriques
- Instituto Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
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Schmidt SP, Corydon TJ, Pedersen CB, Bross P, Gregersen N. Misfolding of short-chain acyl-CoA dehydrogenase leads to mitochondrial fission and oxidative stress. Mol Genet Metab 2010; 100:155-62. [PMID: 20371198 DOI: 10.1016/j.ymgme.2010.03.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2010] [Accepted: 03/14/2010] [Indexed: 11/20/2022]
Abstract
Short-chain acyl-CoA dehydrogenase deficiency (SCADD) is a rare inherited disorder of the mitochondrial beta-oxidation of fatty acids. Patients with SCADD present mainly with symptoms of neuromuscular character. In order to investigate factors involved in the pathogenesis, we studied a disease-associated variant of the SCAD protein (p.Arg83Cys, c.319C>T), which is known to compromise SCAD protein folding. We investigated the consequences of overexpressing the misfolded mitochondrial protein, and thus determined whether the misfolded p.Arg83Cys SCAD proteins can elicit a toxic reaction. Human astrocytes were transiently transfected with either wild-type or p.Arg83Cys encoding cDNA, and analyzed for insoluble proteins/aggregate-formation, alterations in mitochondrial morphology, and for the presence of reactive oxygen species (ROS) in the mitochondria. The majority of cells overexpressing the p.Arg83Cys SCAD variant protein presented with an altered mitochondrial morphology of a grain-like structure, whereas the majority of the cells overexpressing wild-type SCAD presented with a normal thread-like mitochondrial reticulum. We found this grain-like structure to be associated with an increased amount of ROS. The mitochondrial morphology change was partly alleviated by addition of the mitochondrial targeted antioxidant MitoQ, indicating a ROS-induced mitochondrial fission. We therefore propose that SCAD misfolding leads to production of ROS, which in turn leads to fission and a grain-like structure of the mitochondrial reticulum. This finding indicates a toxic response elicited by misfolded p.Arg83Cys SCAD proteins.
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Affiliation(s)
- S P Schmidt
- Research Unit for Molecular Medicine, Aarhus University Hospital, Skejby, Brendstrupgaardsvej 100, Aarhus N, Denmark.
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Straadt IK, Young JF, Petersen BO, Duus JØ, Gregersen N, Bross P, Oksbjerg N, Bertram HC. Metabolic profiling of heat or anoxic stress in mouse C2C12 myotubes using multinuclear magnetic resonance spectroscopy. Metabolism 2010; 59:814-23. [PMID: 20005546 DOI: 10.1016/j.metabol.2009.09.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 08/19/2009] [Accepted: 09/29/2009] [Indexed: 10/20/2022]
Abstract
In the present study, the metabolic effects of heat and anoxic stress in myotubes from the mouse cell line C2C12 were investigated by using a combination of (13)C, (1)H, and (31)P nuclear magnetic resonance (NMR) spectroscopy and enrichment with [(13)C]-glucose. Both the (13)C and the (1)H NMR spectra showed reduced levels of the amino acids alanine, glutamate, and aspartate after heat or anoxic stress. The decreases were smallest at 42 degrees C, larger at 45 degrees C, and most pronounced after anoxic conditions. In addition, in both the (1)H and the (31)P NMR spectra, decreases in the high-energy phosphate compounds adenosine triphosphate and phosphocreatine with increasing severity of stress were identified. At anoxic conditions, an increase in (13)C-labeled lactate and appearance of glycerol-3-phosphate were observed. Accumulation of lactate and glycerol-3-phosphate is in agreement with a shift to anaerobic metabolism due to inhibition of the aerobic pathway in the mitochondria. Conversely, lower levels of unlabeled ((12)C) lactate were apparent at increasing severity of stress, which indicate that lactate is released from the myotubes to the medium. In conclusion, the metabolites identified in the present study may be useful markers for identifying severity of stress in muscles.
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Affiliation(s)
- Ida K Straadt
- Department of Food Science, Faculty of Agricultural Sciences, University of Aarhus, P.O. Box 50, DK-8830 Tjele, Denmark
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Straadt IK, Young JF, Bross P, Gregersen N, Oksbjerg N, Theil PK, Bertram HC. NMR-based metabonomic investigation of heat stress in myotubes reveals a time-dependent change in the metabolites. J Agric Food Chem 2010; 58:6376-6386. [PMID: 20429597 DOI: 10.1021/jf904197u] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
NMR-based metabonomics was applied to elucidate the time-dependent stress responses in mouse myotubes after heat exposure of either 42 or 45 degrees C for 1 h. Principal component analysis (PCA) revealed that the gradual time-dependent changes in metabolites contributing to the clustering and separation of the control samples from the different time points after heat stress primarily are in the metabolites glucose, leucine, lysine, phenylalanine, creatine, glutamine, and acetate. In addition, PC scores revealed a maximum change in metabolite composition 4 h after the stress exposure; thereafter, samples returned toward control samples, however, without reaching the control samples even 10 h after stress. The results also indicate that the myotubes efficiently regulate the pH level by release of lactate to the culture medium at a heat stress level of 42 degrees C, which is a temperature level reached in muscles of pigs during exposure to slaughter stress.
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Affiliation(s)
- Ida K Straadt
- Department of Food Science, Faculty of Agricultural Sciences, Aarhus University, Blichers Alle 20, PO Box 50, DK-8830 Tjele, Denmark
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Straadt IK, Young JF, Petersen BO, Duus JØ, Gregersen N, Bross P, Oksbjerg N, Theil PK, Bertram HC. Oxidative stress-induced metabolic changes in mouse C2C12 myotubes studied with high-resolution 13C, 1H, and 31P NMR spectroscopy. J Agric Food Chem 2010; 58:1918-1926. [PMID: 20073468 DOI: 10.1021/jf903505a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In this study, stress in relation to slaughter was investigated in a model system by the use of (13)C, (1)H, and (31)P nuclear magnetic resonance (NMR) spectroscopy for elucidating changes in the metabolites in C2C12 myotubes exposed to H(2)O(2)-induced stress. Oxidative stress resulted in lower levels of several metabolites, mainly amino acids; however, higher levels of alanine were apparent in the (13)C spectra after incubation with [(13)C(1)]glucose. In the (13)C spectra [(13)C(3)]lactate tended to increase after exposure to increasing concentrations of H(2)O(2); conversely, a tendency to lower levels of the unlabeled ((12)C) lactate were identified in the (1)H spectra after stress exposure. These data indicate an increase in de novo synthesis of alanine, concomitant with a release of lactate from the myotubes to the medium at oxidative stress conditions. The changes in the metabolite levels could possibly be useful as markers for meat quality traits.
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Affiliation(s)
- Ida K Straadt
- Department of Food Science, Faculty of Agricultural Sciences, Aarhus University, DK-8830 Tjele, Denmark
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Bross P, Palmfeldt J, Hansen J, Vang S, Gregersen N. Measuring consequences of protein misfolding and cellular stress using OMICS techniques. Methods Mol Biol 2010; 648:119-135. [PMID: 20700709 DOI: 10.1007/978-1-60761-756-3_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The ambition to measure all or at least a significant fraction of relevant molecules in a cell culture or tissue sample has reached possible realization with the development of the so-called OMICS technologies. We will here briefly review current technologies and give examples of their applications in investigations related to protein misfolding diseases. We will primarily cover the classical OMICS categories GENOMICS, TRANSCRIPTOMICS, METABOLOMICS, and with some more detail PROTEOMICS. These techniques are in most cases performed by dedicated core facilities or commercial services. We will give an assessment of uses as well as limitations of these technologies supported by examples of their application in research related to protein misfolding. We will further briefly discuss genome-wide RNA interference and finally touch on bioinformatics, because the huge amounts of data typically collected with OMICS techniques requires the application of specific software to handle and stratify the data sets. Today, most biologists using OMICS-techniques must, at least in part, be able to analyze their own data using user-friendly web-based tools.
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Abstract
A central part of the research in protein misfolding and its associated disorders is the development of treatment strategies based on ensuring cellular protein homeostasis. This often includes testing chemical substances or drugs for their ability to counteract protein misfolding processes and to promote correct folding. Such investigations also include assessment of how the tested chemical substances affect cellular viability, that is, their cytotoxic effect. Investigations of cytotoxicity often require testing several different concentrations and drug exposure times using cells in culture. It is therefore attractive to use a viability test that permits the analysis of many samples with little handling time. This protocol describes a simple and fast methodology to analyze viability of lymphoblastoid cells and to test putative cytotoxic effects associated with exposure to a chemical substance, here exemplified by celastrol. The natural substance celastrol has been used for many years in traditional Chinese medicine and has subsequently been shown to induce transcription of genes encoding molecular chaperones (heat shock proteins) that are involved in promoting folding of cellular proteins. The well-described colorimetric tetrazolium salt (MTT) assay, which monitors metabolic activity of cultured cells, was adapted to analyze the viability of cells exposed to celastrol. After having established a suitable cell seeding density, the dose-dependence and time-course of viability reduction of lymphoblastoid cells treated with celastrol were determined. It was found that 4- and 24-h exposure to 0.8 microM celastrol reduced the viability of lymphoblastoid cells, with the most severe effect observed at 24 h with MTT reductions approaching 30% of non-exposed cells. For a series of incubations for 24 h, it was found that concentrations as low as 0.2 microM were sufficient to affect the viability, and celastrol concentrations of 0.5 microM reduced the MTT reduction rate to approximately half the level displayed by cells receiving vehicle alone.
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Palmfeldt J, Vang S, Stenbroen V, Pedersen CB, Christensen JH, Bross P, Gregersen N. Mitochondrial proteomics on human fibroblasts for identification of metabolic imbalance and cellular stress. Proteome Sci 2009; 7:20. [PMID: 19476632 PMCID: PMC2695441 DOI: 10.1186/1477-5956-7-20] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [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: 12/09/2008] [Accepted: 05/28/2009] [Indexed: 01/17/2023] Open
Abstract
Background Mitochondrial proteins are central to various metabolic activities and are key regulators of apoptosis. Disturbance of mitochondrial proteins is therefore often associated with disease. Large scale protein data are required to capture the mitochondrial protein levels and mass spectrometry based proteomics is suitable for generating such data. To study the relative quantities of mitochondrial proteins in cells from cultivated human skin fibroblasts we applied a proteomic method based on nanoLC-MS/MS analysis of iTRAQ-labeled peptides. Results When fibroblast cultures were exposed to mild metabolic stress – by cultivation in galactose medium- the amount of mitochondria appeared to be maintained whereas the levels of individual proteins were altered. Proteins of respiratory chain complex I and IV were increased together with NAD+-dependent isocitrate dehydrogenase of the citric acid cycle illustrating cellular strategies to cope with altered energy metabolism. Furthermore, quantitative protein data, with a median standard error below 6%, were obtained for the following mitochondrial pathways: fatty acid oxidation, citric acid cycle, respiratory chain, antioxidant systems, amino acid metabolism, mitochondrial translation, protein quality control, mitochondrial morphology and apoptosis. Conclusion The robust analytical platform in combination with a well-defined compendium of mitochondrial proteins allowed quantification of single proteins as well as mapping of entire pathways. This enabled characterization of the interplay between metabolism and stress response in human cells exposed to mild stress.
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Affiliation(s)
- Johan Palmfeldt
- Institute of Clinical Medicine, Aarhus University Hospital, University of Aarhus, Denmark.
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