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Silva DO, Fernandes Júnior GA, Fonseca LFS, Mota LFM, Bresolin T, Carvalheiro R, de Albuquerque LG. Genome-wide association study for stayability at different calvings in Nellore beef cattle. BMC Genomics 2024; 25:93. [PMID: 38254039 PMCID: PMC10804543 DOI: 10.1186/s12864-024-10020-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 01/16/2024] [Indexed: 01/24/2024] Open
Abstract
BACKGROUNDING Stayability, which may be defined as the probability of a cow remaining in the herd until a reference age or at a specific number of calvings, is usually measured late in the animal's life. Thus, if used as selection criteria, it will increase the generation interval and consequently might decrease the annual genetic gain. Measuring stayability at an earlier age could be a reasonable strategy to avoid this problem. In this sense, a better understanding of the genetic architecture of this trait at different ages and/or at different calvings is important. This study was conducted to identify possible regions with major effects on stayability measured considering different numbers of calvings in Nellore cattle as well as pathways that can be involved in its expression throughout the female's productive life. RESULTS The top 10 most important SNP windows explained, on average, 17.60% of the genetic additive variance for stayability, varying between 13.70% (at the eighth calving) and 21% (at the fifth calving). These SNP windows were located on 17 chromosomes (1, 2, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 18, 19, 20, 27, and 28), and they harbored a total of 176 annotated genes. The functional analyses of these genes, in general, indicate that the expression of stayability from the second to the sixth calving is mainly affected by genetic factors related to reproductive performance, and nervous and immune systems. At the seventh and eighth calvings, genes and pathways related to animal health, such as density bone and cancer, might be more relevant. CONCLUSION Our results indicate that part of the target genomic regions in selecting for stayability at earlier ages (from the 2th to the 6th calving) would be different than selecting for this trait at later ages (7th and 8th calvings). While the expression of stayability at earlier ages appeared to be more influenced by genetic factors linked to reproductive performance together with an overall health/immunity, at later ages genetic factors related to an overall animal health gain relevance. These results support that selecting for stayability at earlier ages (perhaps at the second calving) could be applied, having practical implications in breeding programs since it could drastically reduce the generation interval, accelerating the genetic progress.
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Affiliation(s)
- Diogo Osmar Silva
- Animal Science Department, School of Agricultural and Veterinary Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil.
| | - Gerardo Alves Fernandes Júnior
- Animal Science Department, School of Agricultural and Veterinary Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Larissa Fernanda Simielli Fonseca
- Animal Science Department, School of Agricultural and Veterinary Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Lúcio Flávio Macedo Mota
- Animal Science Department, School of Agricultural and Veterinary Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Tiago Bresolin
- Animal Science Department, School of Agricultural and Veterinary Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Roberto Carvalheiro
- Animal Science Department, School of Agricultural and Veterinary Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Lucia Galvão de Albuquerque
- Animal Science Department, School of Agricultural and Veterinary Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil.
- National Council for Scientific and Technological Development (CNPq), Brasília, Brazil.
- Present address: Departamento de Zootecnia, Via de acesso Paulo Donato Castellane s/n., São Paulo, Jaboticabal, CEP: 14884-900, Brazil.
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Avrutsky MI, Lawson JM, Smart JE, Chen CW, Troy CM. Noninvasive Ophthalmic Imaging Measures Retinal Degeneration and Vision Deficits in Ndufs4-/- Mouse Model of Mitochondrial Complex I Deficiency. Transl Vis Sci Technol 2022; 11:5. [PMID: 35921115 PMCID: PMC9360534 DOI: 10.1167/tvst.11.8.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To characterize postnatal ocular pathology in a Ndufs4−/− mouse model of complex I deficiency using noninvasive retinal imaging and visual testing. Methods Ndufs4−/− mice and wild-type (WT) littermates were analyzed at 3, 5, and 7 weeks postnatal. Retinal morphology was visualized by optical coherence tomography (OCT). OCT images were analyzed for changes in retinal thickness and reflectivity profiles. Visual function was assessed by electroretinogram (ERG) and optomotor reflex (OMR). Results Ndufs4−/− animals have normal OCT morphology at weaning and develop inner plexiform layer atrophy over weeks 5 to 7. Outer retinal layers show hyporeflectivity of the external limiting membrane (ELM) and photoreceptor ellipsoid zone (EZ). Retinal function is impaired at 3 weeks, with profound deficits in b-wave, a-wave, and oscillatory potential amplitudes. The b-wave and oscillatory potential implicit times are delayed, but the a-wave implicit time is unaffected. Ndufs4−/− animals have normal OMR at 3 weeks and present with increasing acuity and contrast OMR deficits at 5 and 7 weeks. Physiological thinning of inner retinal layers, attenuation of ELM reflectivity, and attenuation of ERG b- and a-wave amplitudes occur in WT C57BL/6 littermates between weeks 3 and 7. Conclusions Noninvasive ocular imaging captures early-onset retinal degeneration in Ndufs4−/− mice and is a tractable approach for investigating retinal pathology subsequent to complex I deficiency. Translational Relevance Ophthalmic imaging captures clinically relevant measures of retinal disease in a fast-progressing mouse model of complex I deficiency consistent with human Leigh syndrome.
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Affiliation(s)
- Maria I Avrutsky
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Jacqueline M Lawson
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Jade E Smart
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Claire W Chen
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Carol M Troy
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA.,Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA.,The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
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3
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van de Wal M, Adjobo-Hermans M, Keijer J, Schirris T, Homberg J, Wieckowski MR, Grefte S, van Schothorst EM, van Karnebeek C, Quintana A, Koopman WJH. Ndufs4 knockout mouse models of Leigh syndrome: pathophysiology and intervention. Brain 2021; 145:45-63. [PMID: 34849584 PMCID: PMC8967107 DOI: 10.1093/brain/awab426] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 10/25/2021] [Accepted: 11/11/2021] [Indexed: 11/14/2022] Open
Abstract
Mitochondria are small cellular constituents that generate cellular energy (ATP) by oxidative phosphorylation (OXPHOS). Dysfunction of these organelles is linked to a heterogeneous group of multisystemic disorders, including diabetes, cancer, ageing-related pathologies and rare mitochondrial diseases. With respect to the latter, mutations in subunit-encoding genes and assembly factors of the first OXPHOS complex (complex I) induce isolated complex I deficiency and Leigh syndrome. This syndrome is an early-onset, often fatal, encephalopathy with a variable clinical presentation and poor prognosis due to the lack of effective intervention strategies. Mutations in the nuclear DNA-encoded NDUFS4 gene, encoding the NADH:ubiquinone oxidoreductase subunit S4 (NDUFS4) of complex I, induce ‘mitochondrial complex I deficiency, nuclear type 1’ (MC1DN1) and Leigh syndrome in paediatric patients. A variety of (tissue-specific) Ndufs4 knockout mouse models were developed to study the Leigh syndrome pathomechanism and intervention testing. Here, we review and discuss the role of complex I and NDUFS4 mutations in human mitochondrial disease, and review how the analysis of Ndufs4 knockout mouse models has generated new insights into the MC1ND1/Leigh syndrome pathomechanism and its therapeutic targeting.
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Affiliation(s)
- Melissa van de Wal
- Department of Pediatrics, Amalia Children's Hospital, RIMLS, RCMM, Radboudumc, Nijmegen, The Netherlands
| | - Merel Adjobo-Hermans
- Department of Biochemistry (286), RIMLS, RCMM, Radboudumc, Nijmegen, The Netherlands
| | - Jaap Keijer
- Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands
| | - Tom Schirris
- Department of Pharmacology and Toxicology, RIMLS, RCMM, Radboudumc, Nijmegen, The Netherlands
| | - Judith Homberg
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Radboudumc, Nijmegen, The Netherlands
| | - Mariusz R Wieckowski
- Laboratory of Mitochondrial Biology and Metabolism, Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Sander Grefte
- Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands
| | | | - Clara van Karnebeek
- Department of Pediatrics, Amalia Children's Hospital, RIMLS, RCMM, Radboudumc, Nijmegen, The Netherlands.,Department of Pediatrics, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Albert Quintana
- Mitochondrial Neuropathology Laboratory, Institut de Neurociències and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Werner J H Koopman
- Department of Pediatrics, Amalia Children's Hospital, RIMLS, RCMM, Radboudumc, Nijmegen, The Netherlands.,Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands
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Accessory Subunits of the Matrix Arm of Mitochondrial Complex I with a Focus on Subunit NDUFS4 and Its Role in Complex I Function and Assembly. Life (Basel) 2021; 11:life11050455. [PMID: 34069703 PMCID: PMC8161149 DOI: 10.3390/life11050455] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/13/2021] [Accepted: 05/14/2021] [Indexed: 12/19/2022] Open
Abstract
NADH:ubiquinone-oxidoreductase (complex I) is the largest membrane protein complex of the respiratory chain. Complex I couples electron transfer to vectorial proton translocation across the inner mitochondrial membrane. The L shaped structure of complex I is divided into a membrane arm and a matrix arm. Fourteen central subunits are conserved throughout species, while some 30 accessory subunits are typically found in eukaryotes. Complex I dysfunction is associated with mutations in the nuclear and mitochondrial genome, resulting in a broad spectrum of neuromuscular and neurodegenerative diseases. Accessory subunit NDUFS4 in the matrix arm is a hot spot for mutations causing Leigh or Leigh-like syndrome. In this review, we focus on accessory subunits of the matrix arm and discuss recent reports on the function of accessory subunit NDUFS4 and its interplay with NDUFS6, NDUFA12, and assembly factor NDUFAF2 in complex I assembly.
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Blackout in the powerhouse: clinical phenotypes associated with defects in the assembly of OXPHOS complexes and the mitoribosome. Biochem J 2021; 477:4085-4132. [PMID: 33151299 PMCID: PMC7657662 DOI: 10.1042/bcj20190767] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/29/2020] [Accepted: 10/05/2020] [Indexed: 12/26/2022]
Abstract
Mitochondria produce the bulk of the energy used by almost all eukaryotic cells through oxidative phosphorylation (OXPHOS) which occurs on the four complexes of the respiratory chain and the F1–F0 ATPase. Mitochondrial diseases are a heterogenous group of conditions affecting OXPHOS, either directly through mutation of genes encoding subunits of OXPHOS complexes, or indirectly through mutations in genes encoding proteins supporting this process. These include proteins that promote assembly of the OXPHOS complexes, the post-translational modification of subunits, insertion of cofactors or indeed subunit synthesis. The latter is important for all 13 of the proteins encoded by human mitochondrial DNA, which are synthesised on mitochondrial ribosomes. Together the five OXPHOS complexes and the mitochondrial ribosome are comprised of more than 160 subunits and many more proteins support their biogenesis. Mutations in both nuclear and mitochondrial genes encoding these proteins have been reported to cause mitochondrial disease, many leading to defective complex assembly with the severity of the assembly defect reflecting the severity of the disease. This review aims to act as an interface between the clinical and basic research underpinning our knowledge of OXPHOS complex and ribosome assembly, and the dysfunction of this process in mitochondrial disease.
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Arabidopsis thaliana alternative dehydrogenases: a potential therapy for mitochondrial complex I deficiency? Perspectives and pitfalls. Orphanet J Rare Dis 2019; 14:236. [PMID: 31665043 PMCID: PMC6821020 DOI: 10.1186/s13023-019-1185-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/30/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Complex I (CI or NADH:ubiquinone oxidoreductase) deficiency is the most frequent cause of mitochondrial respiratory chain defect. Successful attempts to rescue CI function by introducing an exogenous NADH dehydrogenase, such as the NDI1 from Saccharomyces cerevisiae (ScNDI1), have been reported although with drawbacks related to competition with CI. In contrast to ScNDI1, which is permanently active in yeast naturally devoid of CI, plant alternative NADH dehydrogenases (NDH-2) support the oxidation of NADH only when the CI is metabolically inactive and conceivably when the concentration of matrix NADH exceeds a certain threshold. We therefore explored the feasibility of CI rescue by NDH-2 from Arabidopsis thaliana (At) in human CI defective fibroblasts. RESULTS We showed that, other than ScNDI1, two different NDH-2 (AtNDA2 and AtNDB4) targeted to the mitochondria were able to rescue CI deficiency and decrease oxidative stress as indicated by a normalization of SOD activity in human CI-defective fibroblasts. We further demonstrated that when expressed in human control fibroblasts, AtNDA2 shows an affinity for NADH oxidation similar to that of CI, thus competing with CI for the oxidation of NADH as opposed to our initial hypothesis. This competition reduced the amount of ATP produced per oxygen atom reduced to water by half in control cells. CONCLUSIONS In conclusion, despite their promising potential to rescue CI defects, due to a possible competition with remaining CI activity, plant NDH-2 should be regarded with caution as potential therapeutic tools for human mitochondrial diseases.
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Di Meo I, Marchet S, Lamperti C, Zeviani M, Viscomi C. AAV9-based gene therapy partially ameliorates the clinical phenotype of a mouse model of Leigh syndrome. Gene Ther 2017; 24:661-667. [PMID: 28753212 PMCID: PMC5658670 DOI: 10.1038/gt.2017.53] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 04/18/2017] [Accepted: 06/13/2017] [Indexed: 02/02/2023]
Abstract
Leigh syndrome (LS) is the most common infantile mitochondrial encephalopathy. No treatment is currently available for this condition. Mice lacking Ndufs4, encoding NADH: ubiquinone oxidoreductase iron-sulfur protein 4 (NDUFS4) recapitulates the main findings of complex I (cI)-related LS, including severe multisystemic cI deficiency and progressive neurodegeneration. In order to develop a gene therapy approach for LS, we used here an AAV2/9 vector carrying the human NDUFS4 coding sequence (hNDUFS4). We administered AAV2/9-hNDUFS4 by intravenous (IV) and/or intracerebroventricular (ICV) routes to either newborn or young Ndufs4-/- mice. We found that IV administration alone was only able to correct the cI deficiency in peripheral organs, whereas ICV administration partially corrected the deficiency in the brain. However, both treatments failed to improve the clinical phenotype or to prolong the lifespan of Ndufs4-/- mice. In contrast, combined IV and ICV treatments resulted, along with increased cI activity, in the amelioration of the rotarod performance and in a significant prolongation of the lifespan. Our results indicate that extraneurological organs have an important role in LS pathogenesis and provide an insight into current limitations of adeno-associated virus (AAV)-mediated gene therapy in multisystem disorders. These findings warrant future investigations to develop new vectors able to efficiently target multiple organs.
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Affiliation(s)
- I Di Meo
- IRCCS Foundation Neurological Institute ‘C. Besta’, Milan, Italy
| | - S Marchet
- IRCCS Foundation Neurological Institute ‘C. Besta’, Milan, Italy
| | - C Lamperti
- IRCCS Foundation Neurological Institute ‘C. Besta’, Milan, Italy
| | - M Zeviani
- University of Cambridge/Medical Research Council, Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge, CB2 0XY, UK
| | - C Viscomi
- University of Cambridge/Medical Research Council, Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge, CB2 0XY, UK
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Wang M, Huang YP, Wu H, Song K, Wan C, Chi AN, Xiao YM, Zhao XY. Mitochondrial complex I deficiency leads to the retardation of early embryonic development in Ndufs4 knockout mice. PeerJ 2017; 5:e3339. [PMID: 28533980 PMCID: PMC5438584 DOI: 10.7717/peerj.3339] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 04/20/2017] [Indexed: 11/25/2022] Open
Abstract
Background The NDUFS4 gene encodes an 18-kD subunit of mitochondria complex I, and mutations in this gene lead to the development of a severe neurodegenerative disease called Leigh syndrome (LS) in humans. To investigate the disease phenotypes and molecular mechanisms of Leigh syndrome, the Ndufs4 knockout (KO) mouse has been widely used as a novel animal model. Because the homozygotes cannot survive beyond child-bearing age, whether Ndufs4 and mitochondrial complex I influence early embryonic development remains unknown. In our study, we attempted to investigate embryonic development in Ndufs4 KO mice, which can be regarded as a Leigh disease model and were created through the CRISPR (clustered regularly interspaced short palindromic repeat) and Cas9 (CRISPR associated)-mediated genome editing system. Methods We first designed a single guide RNA (sgRNA) targeting exon 2 of Ndufs4 to delete the NDUFS4 protein in mouse embryos to mimic Leigh syndrome. Then, we described the phenotypes of our mouse model by forced swimming and the open-field test as well as by assessing other behavioral characteristics. Intracytoplasmic sperm injection (ICSI) was performed to obtain KO embryos to test the influence of NDUFS4 deletion on early embryonic development. Results In this study, we first generated Ndufs4 KO mice with physical and behavioral phenotypes similar to Leigh syndrome using the CRISPR/Cas9 system. The low developmental rate of KO embryos that were derived from knockout gametes indicated that the absence of NDUFS4 impaired the development of preimplantation embryos. Discussion In this paper, we first obtained Ndufs4 KO mice that could mimic Leigh syndrome using the CRISPR/Cas9 system. Then, we identified the role of NDUFS4 in early embryonic development, shedding light on its roles in the respiratory chain and fertility. Our model provides a useful tool with which to investigate the function of Ndufs4. Although the pathological mechanisms of the disease need to be discovered, it helps to understand the pathogenesis of NDUFS4 deficiency in mice and its effects on human diseases.
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Affiliation(s)
- Mei Wang
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal University, Changsha, China.,Department of Developmental Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Ya-Ping Huang
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal University, Changsha, China.,Department of Developmental Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Han Wu
- Department of Developmental Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Ke Song
- School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Cong Wan
- Department of Developmental Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - A-Ni Chi
- Department of Developmental Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Ya-Mei Xiao
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal University, Changsha, China
| | - Xiao-Yang Zhao
- Department of Developmental Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
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9
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A novel NDUFS4 frameshift mutation causes Leigh disease in the Hutterite population. Am J Med Genet A 2016; 173:596-600. [DOI: 10.1002/ajmg.a.37983] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 09/05/2016] [Indexed: 11/07/2022]
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Ortigoza-Escobar JD, Oyarzabal A, Montero R, Artuch R, Jou C, Jiménez C, Gort L, Briones P, Muchart J, López-Gallardo E, Emperador S, Pesini ER, Montoya J, Pérez B, Rodríguez-Pombo P, Pérez-Dueñas B. Ndufs4 related Leigh syndrome: A case report and review of the literature. Mitochondrion 2016; 28:73-8. [DOI: 10.1016/j.mito.2016.04.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 12/30/2022]
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Cameron JM, MacKay N, Feigenbaum A, Tarnopolsky M, Blaser S, Robinson BH, Schulze A. Exome sequencing identifies complex I NDUFV2 mutations as a novel cause of Leigh syndrome. Eur J Paediatr Neurol 2015; 19:525-32. [PMID: 26008862 DOI: 10.1016/j.ejpn.2015.05.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 02/12/2015] [Accepted: 05/05/2015] [Indexed: 12/30/2022]
Abstract
BACKGROUND Two siblings with hypertrophic cardiomyopathy and brain atrophy were diagnosed with Complex I deficiency based on low enzyme activity in muscle and high lactate/pyruvate ratio in fibroblasts. METHODS Whole exome sequencing results of fibroblast gDNA from one sibling was narrowed down to 190 SNPs or In/Dels in 185 candidate genes by selecting non-synonymous coding sequence base pair changes that were not present in the SNP database. RESULTS Two compound heterozygous mutations were identified in both siblings in NDUFV2, encoding the 24 kDa subunit of Complex I. The intronic mutation (c.IVS2 + 1delGTAA) is disease causing and has been reported before. The other mutation is novel (c.669_670insG, p.Ser224Valfs*3) and predicted to cause a pathogenic frameshift in the protein. Subsequent investigation of 10 probands with complex I deficiency from different families revealed homozygosity for the intronic c.IVS2 + 1delGTAA mutation in a second, consanguineous family. In this family three of five siblings were affected. Interestingly, they presented with Leigh syndrome but no cardiac involvement. The same genotype had been reported previously in a two families but presenting with hypertrophic cardiomyopathy, trunk hypotonia and encephalopathy. CONCLUSION We have identified NDUFV2 mutations in two families with Complex I deficiency, including a novel mutation. The diagnosis of Leigh syndrome expands the clinical phenotypes associated with the c.IVS2 + 1delGTAA mutation in this gene.
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Affiliation(s)
- Jessie M Cameron
- Genetics & Genome Biology Program, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, ON M5G 0A4, Canada.
| | - Nevena MacKay
- Department of Paediatric Laboratory Medicine, The Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | - Annette Feigenbaum
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children and University of Toronto, Toronto, ON M5G 1X8, Canada.
| | - Mark Tarnopolsky
- Department of Pediatrics, McMaster University Medical Center, Hamilton, ON L8N 3Z5, Canada.
| | - Susan Blaser
- Department of Radiology, The Hospital for Sick Children and University of Toronto, ON M5G 1X8, Canada.
| | - Brian H Robinson
- Genetics & Genome Biology Program, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.
| | - Andreas Schulze
- Genetics & Genome Biology Program, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Division of Clinical and Metabolic Genetics, The Hospital for Sick Children and University of Toronto, Toronto, ON M5G 1X8, Canada.
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12
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Johnson SC, Yanos ME, Bitto A, Castanza A, Gagnidze A, Gonzalez B, Gupta K, Hui J, Jarvie C, Johnson BM, Letexier N, McCanta L, Sangesland M, Tamis O, Uhde L, Van Den Ende A, Rabinovitch PS, Suh Y, Kaeberlein M. Dose-dependent effects of mTOR inhibition on weight and mitochondrial disease in mice. Front Genet 2015; 6:247. [PMID: 26257774 PMCID: PMC4510413 DOI: 10.3389/fgene.2015.00247] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/06/2015] [Indexed: 11/13/2022] Open
Abstract
Rapamycin extends lifespan and attenuates age-related pathologies in mice when administered through diet at 14 parts per million (PPM). Recently, we reported that daily intraperitoneal injection of rapamycin at 8 mg/kg attenuates mitochondrial disease symptoms and progression in the Ndufs4 knockout mouse model of Leigh Syndrome. Although rapamycin is a widely used pharmaceutical agent dosage has not been rigorously examined and no dose-response profile has been established. Given these observations we sought to determine if increased doses of oral rapamycin would result in more robust impact on mTOR driven parameters. To test this hypothesis, we compared the effects of dietary rapamycin at doses ranging from 14 to 378 PPM on developmental weight in control and Ndufs4 knockout mice and on health and survival in the Ndufs4 knockout model. High dose rapamycin was well tolerated, dramatically reduced weight gain during development, and overcame gender differences. The highest oral dose, approximately 27-times the dose shown to extend murine lifespan, increased survival in Ndufs4 knockout mice similarly to daily rapamycin injection without observable adverse effects. These findings have broad implications for the effective use of rapamycin in murine studies and for the translational potential of rapamycin in the treatment of mitochondrial disease. This data, further supported by a comparison of available literature, suggests that 14 PPM dietary rapamycin is a sub-optimal dose for targeting mTOR systemically in mice. Our findings suggest that the role of mTOR in mammalian biology may be broadly underestimated when determined through treatment with rapamycin at commonly used doses.
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Affiliation(s)
- Simon C Johnson
- Department of Pathology, University of Washington Seattle, WA, USA ; Department of Genetics, Albert Einstein College of Medicine New York, NY, USA
| | - Melana E Yanos
- Department of Pathology, University of Washington Seattle, WA, USA ; Department of Psychology, University of Washington Seattle, WA, USA
| | - Alessandro Bitto
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Anthony Castanza
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Arni Gagnidze
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Brenda Gonzalez
- Department of Genetics, Albert Einstein College of Medicine New York, NY, USA
| | - Kanav Gupta
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Jessica Hui
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Conner Jarvie
- Department of Pathology, University of Washington Seattle, WA, USA
| | | | - Nicolas Letexier
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Lanny McCanta
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Maya Sangesland
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Oliver Tamis
- Department of Pathology, University of Washington Seattle, WA, USA
| | - Lauren Uhde
- Department of Pathology, University of Washington Seattle, WA, USA
| | | | | | - Yousin Suh
- Department of Genetics, Albert Einstein College of Medicine New York, NY, USA
| | - Matt Kaeberlein
- Department of Pathology, University of Washington Seattle, WA, USA
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Torraco A, Peralta S, Iommarini L, Diaz F. Mitochondrial Diseases Part I: mouse models of OXPHOS deficiencies caused by defects in respiratory complex subunits or assembly factors. Mitochondrion 2015; 21:76-91. [PMID: 25660179 DOI: 10.1016/j.mito.2015.01.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 11/22/2014] [Accepted: 01/05/2015] [Indexed: 10/24/2022]
Abstract
Mitochondrial disorders are the most common inborn errors of metabolism affecting the oxidative phosphorylation system (OXPHOS). Because of the poor knowledge of the pathogenic mechanisms, a cure for these disorders is still unavailable and all the treatments currently in use are supportive more than curative. Therefore, in the past decade a great variety of mouse models have been developed to assess the in vivo function of several mitochondrial proteins involved in human diseases. Due to the genetic and physiological similarity to humans, mice represent reliable models to study the pathogenic mechanisms of mitochondrial disorders and are precious to test new therapeutic approaches. Here we summarize the features of several mouse models of mitochondrial diseases directly related to defects in subunits of the OXPHOS complexes or in assembly factors. We discuss how these models recapitulate many human conditions and how they have contributed to the understanding of mitochondrial function in health and disease.
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Affiliation(s)
- Alessandra Torraco
- Unit for Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital, IRCCS, Viale di San Paolo, 15-00146 Rome, Italy.
| | - Susana Peralta
- Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA.
| | - Luisa Iommarini
- Department of Pharmacy and Biotechnology (FABIT), University of Bologna, Via Irnerio 42, 40126 Bologna, Italy.
| | - Francisca Diaz
- Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA.
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14
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Ruhoy IS, Saneto RP. The genetics of Leigh syndrome and its implications for clinical practice and risk management. APPLICATION OF CLINICAL GENETICS 2014; 7:221-34. [PMID: 25419155 PMCID: PMC4235479 DOI: 10.2147/tacg.s46176] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Leigh syndrome, also referred to as subacute necrotizing encephalomyelopathy, is a severe, early-onset neurodegenerative disorder that is relentlessly progressive and devastating to both the patient and the patient’s family. Attributed to the ultimate failure of the mitochondrial respiratory chain, once it starts, the disease often results in the regression of both mental and motor skills, leading to disability and rapid progression to death. It is a mitochondrial disorder with both phenotypic and genetic heterogeneity. The cause of death is most often respiratory failure, but there are a whole host of complications, including refractory seizures, that may further complicate morbidity and mortality. The symptoms may develop slowly or with rapid progression, usually associated with age of onset. Although the disease is usually diagnosed within the first year of life, it is important to note that recent studies reveal phenotypic heterogeneity, with some patients having evidence of in utero presentation and others having adult-onset symptoms.
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Affiliation(s)
- Ilene S Ruhoy
- Division of Pediatric Neurology, Seattle Children's Hospital/University of Washington, Seattle, WA, USA
| | - Russell P Saneto
- Division of Pediatric Neurology, Seattle Children's Hospital/University of Washington, Seattle, WA, USA
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15
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Assereto S, Robbiano A, Di Rocco M, Rossi A, Cassandrini D, Panicucci C, Brigati G, Biancheri R, Bruno C, Minetti C, Trucks H, Sander T, Zara F, Gazzerro E. Functional characterization of the c.462delA mutation in theNDUFS4subunit gene of mitochondrial complex I. Clin Genet 2013; 86:99-101. [DOI: 10.1111/cge.12248] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 07/31/2013] [Accepted: 08/06/2013] [Indexed: 11/28/2022]
Affiliation(s)
- S. Assereto
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
| | - A. Robbiano
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
| | - M. Di Rocco
- Department of Paediatrics, Unit of Rare Diseases; G. Gaslini Institute; Genoa Italy
| | - A. Rossi
- Department of Paediatric Neuroradiology; G. Gaslini Institute; Genoa Italy
| | - D. Cassandrini
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
| | - C. Panicucci
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
| | - G. Brigati
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
| | - R. Biancheri
- Department of Neuroscience; G. Gaslini Institute; Genoa Italy
| | - C. Bruno
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
| | - C. Minetti
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
- Department of Paediatrics; University of Genova; Genoa Italy
- Department of Neuroscience; University of Genova; Genoa Italy
| | - H. Trucks
- Cologne Center for Genomics; University of Cologne; Cologne Germany
| | - T. Sander
- Cologne Center for Genomics; University of Cologne; Cologne Germany
| | - F. Zara
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
| | - E. Gazzerro
- Paediatric Neurology and Muscle Disease Unit; G. Gaslini Institute; Genoa Italy
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16
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Iommarini L, Calvaruso MA, Kurelac I, Gasparre G, Porcelli AM. Complex I impairment in mitochondrial diseases and cancer: Parallel roads leading to different outcomes. Int J Biochem Cell Biol 2013; 45:47-63. [DOI: 10.1016/j.biocel.2012.05.016] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 05/03/2012] [Accepted: 05/24/2012] [Indexed: 02/06/2023]
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17
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Papa S, De Rasmo D. Complex I deficiencies in neurological disorders. Trends Mol Med 2012; 19:61-9. [PMID: 23265841 DOI: 10.1016/j.molmed.2012.11.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 10/18/2012] [Accepted: 11/15/2012] [Indexed: 12/14/2022]
Abstract
Complex I is the point of entry in the mitochondrial electron transport chain for NADH reducing equivalents, and it behaves as a regulatable pacemaker of respiratory ATP production in human cells. Defects in complex I are associated with several human neurological disorders, including primary mitochondrial diseases, Parkinson disease (PD), and Down syndrome, and understanding the activity and regulation of complex I may reveal aspects of the underlying pathogenic mechanisms. Complex I is regulated by cyclic AMP (cAMP) and the protein kinase A (PKA) signal transduction pathway, and elucidating the role of the cAMP/PKA system in regulating complex I and oxygen free radical production provides new perspectives for devising therapeutic strategies for neurological diseases.
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Affiliation(s)
- Sergio Papa
- Institute of Biomembranes and Bioenergetics (IBBE), Consiglio Nazionale delle Ricerche, Bari, Italy.
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18
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Koene S, Rodenburg RJ, van der Knaap MS, Willemsen MAAP, Sperl W, Laugel V, Ostergaard E, Tarnopolsky M, Martin MA, Nesbitt V, Fletcher J, Edvardson S, Procaccio V, Slama A, van den Heuvel LPWJ, Smeitink JAM. Natural disease course and genotype-phenotype correlations in Complex I deficiency caused by nuclear gene defects: what we learned from 130 cases. J Inherit Metab Dis 2012; 35:737-47. [PMID: 22644603 PMCID: PMC3432203 DOI: 10.1007/s10545-012-9492-z] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 04/13/2012] [Accepted: 04/16/2012] [Indexed: 11/29/2022]
Abstract
Mitochondrial complex I is the largest multi-protein enzyme complex of the oxidative phosphorylation system. Seven subunits of this complex are encoded by the mitochondrial and the remainder by the nuclear genome. We review the natural disease course and signs and symptoms of 130 patients (four new cases and 126 from literature) with mutations in nuclear genes encoding structural complex I proteins or those involved in its assembly. Complex I deficiency caused by a nuclear gene defect is usually a non-dysmorphic syndrome, characterized by severe multi-system organ involvement and a poor prognosis. Age at presentation may vary, but is generally within the first year of life. The most prevalent symptoms include hypotonia, nystagmus, respiratory abnormalities, pyramidal signs, dystonia, psychomotor retardation or regression, failure to thrive, and feeding problems. Characteristic symptoms include brainstem involvement, optic atrophy and Leigh syndrome on MRI, either or not in combination with internal organ involvement and lactic acidemia. Virtually all children ultimately develop Leigh syndrome or leukoencephalopathy. Twenty-five percent of the patients died before the age of six months, more than half before the age of two and 75 % before the age of ten years. Some patients showed recovery of certain skills or are still alive in their thirties . No clinical, biochemical, or genetic parameters indicating longer survival were found. No clear genotype-phenotype correlations were observed, however defects in some genes seem to be associated with a better or poorer prognosis, cardiomyopathy, Leigh syndrome or brainstem lesions.
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Affiliation(s)
- S Koene
- Nijmegen Centre for Mitochondrial Disorders, Institute for Genetic and Metabolic Disease, Radboud University Nijmegen Medical Centre, Geert Grooteplein 10, 6500 HB PO BOX 9101, Nijmegen, The Netherlands.
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19
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Assouline Z, Jambou M, Rio M, Bole-Feysot C, de Lonlay P, Barnerias C, Desguerre I, Bonnemains C, Guillermet C, Steffann J, Munnich A, Bonnefont J, Rötig A, Lebre A. A constant and similar assembly defect of mitochondrial respiratory chain complex I allows rapid identification of NDUFS4 mutations in patients with Leigh syndrome. Biochim Biophys Acta Mol Basis Dis 2012; 1822:1062-9. [DOI: 10.1016/j.bbadis.2012.01.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 01/11/2012] [Accepted: 01/25/2012] [Indexed: 12/31/2022]
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20
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Quintana A, Zanella S, Koch H, Kruse SE, Lee D, Ramirez JM, Palmiter RD. Fatal breathing dysfunction in a mouse model of Leigh syndrome. J Clin Invest 2012; 122:2359-68. [PMID: 22653057 DOI: 10.1172/jci62923] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 04/18/2012] [Indexed: 01/27/2023] Open
Abstract
Leigh syndrome (LS) is a subacute necrotizing encephalomyelopathy with gliosis in several brain regions that usually results in infantile death. Loss of murine Ndufs4, which encodes NADH dehydrogenase (ubiquinone) iron-sulfur protein 4, results in compromised activity of mitochondrial complex I as well as progressive neurodegenerative and behavioral changes that resemble LS. Here, we report the development of breathing abnormalities in a murine model of LS. Magnetic resonance imaging revealed hyperintense bilateral lesions in the dorsal brain stem vestibular nucleus (VN) and cerebellum of severely affected mice. The mutant mice manifested a progressive increase in apnea and had aberrant responses to hypoxia. Electrophysiological recordings within the ventral brain stem pre-Bötzinger respiratory complex were also abnormal. Selective inactivation of Ndufs4 in the VN, one of the principle sites of gliosis, also led to breathing abnormalities and premature death. Conversely, Ndufs4 restoration in the VN corrected breathing deficits and prolonged the life span of knockout mice. These data demonstrate that mitochondrial dysfunction within the VN results in aberrant regulation of respiration and contributes to the lethality of Ndufs4-knockout mice.
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Affiliation(s)
- Albert Quintana
- Howard Hughes Medical Institute and Department of Biochemistry, University of Washington, Seattle, WA, USA
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21
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De Rasmo D, Signorile A, Larizza M, Pacelli C, Cocco T, Papa S. Activation of the cAMP cascade in human fibroblast cultures rescues the activity of oxidatively damaged complex I. Free Radic Biol Med 2012; 52:757-64. [PMID: 22198267 DOI: 10.1016/j.freeradbiomed.2011.11.030] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Revised: 11/16/2011] [Accepted: 11/23/2011] [Indexed: 10/14/2022]
Abstract
A study of the relationship between cAMP/PKA-dependent phosphorylation and oxidative damage of subunits of complex I of the mitochondrial respiratory chain is presented. It is shown that, in fibroblast cultures, PKA-mediated phosphorylation of the NDUFS4 subunit of complex I rescues the activity of the oxidatively damaged complex. Evidence is presented showing that this effect is mediated by phosphorylation-dependent exchange of carbonylated NDUFS4 subunit in the assembled complex with the de novo synthesized subunit. These results indicate a potential use for β-adrenoceptor agonists in preventing/reversing the detrimental effects of oxidative stress in the mitochondrial respiratory system.
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Affiliation(s)
- Domenico De Rasmo
- Section of Medical Biochemistry, Department of Basic Medical Sciences, University of Bari, Bari, Italy
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22
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Pagniez-Mammeri H, Loublier S, Legrand A, Bénit P, Rustin P, Slama A. Mitochondrial complex I deficiency of nuclear origin I. Structural genes. Mol Genet Metab 2012; 105:163-72. [PMID: 22142868 DOI: 10.1016/j.ymgme.2011.11.188] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2011] [Revised: 11/09/2011] [Accepted: 11/09/2011] [Indexed: 10/15/2022]
Abstract
Complex I (or NADH-ubiquinone oxidoreductase), is by far the largest respiratory chain complex with 38 subunits nuclearly encoded and 7 subunits encoded by the mitochondrial genome. Its deficiency is the most frequently encountered in mitochondrial disorders. Here, we summarize recent data obtained on architecture of complex I, and review the pathogenic mutations identified to date in nuclear structural complex I genes. The structural NDUFS1, NDUFS2, NDUFV1, and NDUFS4 genes are mutational hot spot genes for isolated complex I deficiency. The majority of the pathogenic mutations are private and the genotype-phenotype correlation is inconsistent in the rare recurrent mutations.
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Affiliation(s)
- Hélène Pagniez-Mammeri
- Laboratoire de Biochimie, APHP Hôpital de Bicêtre, 78 rue du Général Leclerc, 94275 Le Kremlin Bicêtre cedex, France
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23
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Koene S, Willems PHGM, Roestenberg P, Koopman WJH, Smeitink JAM. Mouse models for nuclear DNA-encoded mitochondrial complex I deficiency. J Inherit Metab Dis 2011; 34:293-307. [PMID: 20107904 DOI: 10.1007/s10545-009-9005-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Revised: 09/17/2009] [Accepted: 10/08/2009] [Indexed: 02/08/2023]
Abstract
Mitochondrial diseases are a group of heterogeneous pathologies with decreased cellular energy production as a common denominator. Defects in the oxidative phosphorylation (OXPHOS) system, the most frequent one in humans being isolated complex I deficiency (OMIM 252010), underlie this disturbed-energy generation. As biogenesis of OXPHOS complexes is under dual genetic control, with complex II being the sole exception, mutations in both nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) are found. Increasing knowledge is becoming available with respect to the pathophysiology and cellular consequences of OXPHOS dysfunction. This aids the rational design of new treatment strategies. Recently, the first successful treatment trials were carried out in patient-derived cell lines. In these studies chemical compounds were used that target cellular aberrations induced by complex I dysfunction. Before the field of human clinical trials is entered, it is necessary to study the effects of these compounds with respect to toxicity, pharmacokinetics and therapeutic potential in suitable animal models. Here, we discuss two recent mouse models for nDNA-encoded complex I deficiency and their tissue-specific knock-outs.
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Affiliation(s)
- Saskia Koene
- Department of Paediatrics, Nijmegen Centre for Mitochondrial Disorders, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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24
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Calvo SE, Tucker EJ, Compton AG, Kirby DM, Crawford G, Burtt NP, Rivas M, Guiducci C, Bruno DL, Goldberger OA, Redman MC, Wiltshire E, Wilson CJ, Altshuler D, Gabriel SB, Daly MJ, Thorburn DR, Mootha VK. High-throughput, pooled sequencing identifies mutations in NUBPL and FOXRED1 in human complex I deficiency. Nat Genet 2010; 42:851-8. [PMID: 20818383 PMCID: PMC2977978 DOI: 10.1038/ng.659] [Citation(s) in RCA: 286] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Accepted: 08/11/2010] [Indexed: 12/15/2022]
Abstract
Discovering the molecular basis of mitochondrial respiratory chain disease is challenging given the large number of both mitochondrial and nuclear genes that are involved. We report a strategy of focused candidate gene prediction, high-throughput sequencing and experimental validation to uncover the molecular basis of mitochondrial complex I disorders. We created seven pools of DNA from a cohort of 103 cases and 42 healthy controls and then performed deep sequencing of 103 candidate genes to identify 151 rare variants that were predicted to affect protein function. We established genetic diagnoses in 13 of 60 previously unsolved cases using confirmatory experiments, including cDNA complementation to show that mutations in NUBPL and FOXRED1 can cause complex I deficiency. Our study illustrates how large-scale sequencing, coupled with functional prediction and experimental validation, can be used to identify causal mutations in individual cases.
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Affiliation(s)
- Sarah E Calvo
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, USA
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