Abstract
Skeletal muscle mtDNA of three patients with mitochondrial encephalomyopathy, characterized clinically by myoclonic epilepsy and ragged-red fiber (MERRF) syndrome, has been sequenced to determine the underlying molecular defect(s). An A-to-G substitution of nt 8344 in the tRNA(Lys) gene, a substitution suggested to be associated with MERRF encephalomyopathy, was detected in these patients. Abnormal patterns of mitochondrial translation products were observed in the skeletal muscle of patients, consistent with the expected consequential defect in protein synthesis. The genealogical studies of the three patients, as well as mtDNA from one published MERRF patient and from nine other normal and disease controls, revealed that the tRNA(Lys) mutations in the MERRF patients have arisen independently. These observations provided evidence that the base substitution is a causal mutation for MERRF.
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- Anderson S., Bankier A. T., Barrell B. G., de Bruijn M. H., Coulson A. R., Drouin J., Eperon I. C., Nierlich D. P., Roe B. A., Sanger F. Sequence and organization of the human mitochondrial genome. Nature. 1981 Apr 9;290(5806):457–465. doi: 10.1038/290457a0. [DOI] [PubMed] [Google Scholar]
- Bresolin N., Zeviani M., Bonilla E., Miller R. H., Leech R. W., Shanske S., Nakagawa M., DiMauro S. Fatal infantile cytochrome c oxidase deficiency: decrease of immunologically detectable enzyme in muscle. Neurology. 1985 Jun;35(6):802–812. doi: 10.1212/wnl.35.6.802. [DOI] [PubMed] [Google Scholar]
- Byrne E., Dennett X., Trounce I., Burdon J. Mitochondrial myoneuropathy with respiratory failure and myoclonic epilepsy. A case report with biochemical studies. J Neurol Sci. 1985 Dec;71(2-3):273–281. doi: 10.1016/0022-510x(85)90065-6. [DOI] [PubMed] [Google Scholar]
- Byrne E., Marzuki S., Dennett X. Current perspectives in the study of human mitochondriopathies. Med J Aust. 1988 Jul 4;149(1):30–33. doi: 10.5694/j.1326-5377.1988.tb120480.x. [DOI] [PubMed] [Google Scholar]
- Byrne E., Trounce I., Marzuki S., Dennett X., Berkovic S. F., Davis S., Tanaka M., Ozawa T. Functional respiratory chain studies in mitochondrial cytopathies. Support for mitochondrial DNA heteroplasmy in myoclonus epilepsy and ragged red fibers (MERRF) syndrome. Acta Neuropathol. 1991;81(3):318–323. doi: 10.1007/BF00305874. [DOI] [PubMed] [Google Scholar]
- Byrne E., Trounce I. Oxygen electrode studies with human skeletal muscle mitochondria in vitro. A re-appraisal. J Neurol Sci. 1985 Jul;69(3):319–333. doi: 10.1016/0022-510x(85)90143-1. [DOI] [PubMed] [Google Scholar]
- Chamberlain J. P. Fluorographic detection of radioactivity in polyacrylamide gels with the water-soluble fluor, sodium salicylate. Anal Biochem. 1979 Sep 15;98(1):132–135. doi: 10.1016/0003-2697(79)90716-4. [DOI] [PubMed] [Google Scholar]
- Ching E., Attardi G. High-resolution electrophoretic fractionation and partial characterization of the mitochondrial translation products from HeLa cells. Biochemistry. 1982 Jun 22;21(13):3188–3195. doi: 10.1021/bi00256a024. [DOI] [PubMed] [Google Scholar]
- DiMauro S., Bonilla E., Zeviani M., Servidei S., DeVivo D. C., Schon E. A. Mitochondrial myopathies. J Inherit Metab Dis. 1987;10 (Suppl 1):113–128. doi: 10.1007/BF01812852. [DOI] [PubMed] [Google Scholar]
- Fukuhara N., Tokiguchi S., Shirakawa K., Tsubaki T. Myoclonus epilepsy associated with ragged-red fibres (mitochondrial abnormalities ): disease entity or a syndrome? Light-and electron-microscopic studies of two cases and review of literature. J Neurol Sci. 1980 Jul;47(1):117–133. doi: 10.1016/0022-510x(80)90031-3. [DOI] [PubMed] [Google Scholar]
- Kadenbach B., Jarausch J., Hartmann R., Merle P. Separation of mammalian cytochrome c oxidase into 13 polypeptides by a sodium dodecyl sulfate-gel electrophoretic procedure. Anal Biochem. 1983 Mar;129(2):517–521. doi: 10.1016/0003-2697(83)90586-9. [DOI] [PubMed] [Google Scholar]
- Marzuki S., Sattayasai N., Trounce I., Byrne E. Protein synthesis in mitochondria isolated from human skeletal muscle. Detection of polymorphism in mitochondrial translation products. J Neurol Sci. 1988 Nov;87(2-3):211–219. doi: 10.1016/0022-510x(88)90246-8. [DOI] [PubMed] [Google Scholar]
- Petty R. K., Harding A. E., Morgan-Hughes J. A. The clinical features of mitochondrial myopathy. Brain. 1986 Oct;109(Pt 5):915–938. doi: 10.1093/brain/109.5.915. [DOI] [PubMed] [Google Scholar]
- Saiki R. K., Gelfand D. H., Stoffel S., Scharf S. J., Higuchi R., Horn G. T., Mullis K. B., Erlich H. A. Primer-directed enzymatic amplification of DNA with a thermostable DNA polymerase. Science. 1988 Jan 29;239(4839):487–491. doi: 10.1126/science.2448875. [DOI] [PubMed] [Google Scholar]
- Shoffner J. M., Lott M. T., Lezza A. M., Seibel P., Ballinger S. W., Wallace D. C. Myoclonic epilepsy and ragged-red fiber disease (MERRF) is associated with a mitochondrial DNA tRNA(Lys) mutation. Cell. 1990 Jun 15;61(6):931–937. doi: 10.1016/0092-8674(90)90059-n. [DOI] [PubMed] [Google Scholar]
- Singh G., Lott M. T., Wallace D. C. A mitochondrial DNA mutation as a cause of Leber's hereditary optic neuropathy. N Engl J Med. 1989 May 18;320(20):1300–1305. doi: 10.1056/NEJM198905183202002. [DOI] [PubMed] [Google Scholar]
- Wallace D. C., Zheng X. X., Lott M. T., Shoffner J. M., Hodge J. A., Kelley R. I., Epstein C. M., Hopkins L. C. Familial mitochondrial encephalomyopathy (MERRF): genetic, pathophysiological, and biochemical characterization of a mitochondrial DNA disease. Cell. 1988 Nov 18;55(4):601–610. doi: 10.1016/0092-8674(88)90218-8. [DOI] [PubMed] [Google Scholar]


