Mutation in subdomain G' of mitochondrial elongation factor G1 is associated with combined OXPHOS deficiency in fibroblasts but not in muscle
until further notice
SourceEuropean Journal of Human Genetics, 19, 3, (2011), pp. 275-279
Article / Letter to editor
Display more detailsDisplay less details
Paediatrics - OUD tm 2017
Laboratory of Genetic, Endocrine and Metabolic Diseases
European Journal of Human Genetics
SubjectIGMD 3: Genomic disorders and inherited multi-system disorders; IGMD 3: Genomic disorders and inherited multi-system disorders NCMLS 4: Energy and redox metabolism; IGMD 8: Mitochondrial medicine NCMLS 4: Energy and redox metabolism; IGMD 9: Renal disorder NCMLS 4: Energy and redox metabolism; IGMD 9: Renal disorder NCMLS 5: Membrane transport and intracellular motility; NCMLS 7: Chemical and physical biology; IGMD 8: Mitochondrial medicine NCMLS 4: Energy and redox metabolism; IGMD 9: Renal disorder NCMLS 5: Membrane transport and intracellular motility
The mitochondrial translation system is responsible for the synthesis of 13 proteins required for oxidative phosphorylation (OXPHOS), the major energy-generating process of our cells. Mitochondrial translation is controlled by various nuclear encoded proteins. In 27 patients with combined OXPHOS deficiencies, in whom complex II (the only complex that is entirely encoded by the nuclear DNA) showed normal activities, and mutations in the mitochondrial genome as well as polymerase gamma were excluded, we screened all mitochondrial translation factors for mutations. Here, we report a mutation in mitochondrial elongation factor G1 (GFM1) in a patient affected by severe, rapidly progressive mitochondrial encephalopathy. This mutation is predicted to result in an Arg250Trp substitution in subdomain G' of the elongation factor G1 protein and is presumed to hamper ribosome-dependent GTP hydrolysis. Strikingly, the decrease in enzyme activities of complex I, III and IV detected in patient fibroblasts was not found in muscle tissue. The OXPHOS system defects and the impairment in mitochondrial translation in fibroblasts were rescued by overexpressing wild-type GFM1, establishing the GFM1 defect as the cause of the fatal mitochondrial disease. Furthermore, this study evinces the importance of a thorough diagnostic biochemical analysis of both muscle tissue and fibroblasts in patients suspected to suffer from a mitochondrial disorder, as enzyme deficiencies can be selectively expressed.
Upload full text
Use your RU credentials (u/z-number and password) tolog in with SURFconextto upload a file for processing by the repository team.