Mitochondrial studies in Kearns-Sayre syndrome: normal respiratory chain function with absence of a mitochondrial translation product.
Intact mitochondria were isolated from skeletal muscle of two patients with Kearns-Sayre syndrome (retinitis pigmentosa, heart block, chronic external ophthalmoplegia), and mitochondrial protein translation was measured. Mitochondrial protein synthesis was up to 10 times greater than in control subjects and SDS-polyacrylamide gel electrophoresis revealed absence of a translation product with the mobility of a 5 KDa protein. State 3 respiration rates were normal with site 1 and site 2 substrates, suggesting that the absent protein was not a functional subunit of a respiratory chain complex.
D000328:Adult; D003580:Cytochromes / Q000378:metabolism; D005260:Female; D006801:Humans; D007625:Kearns-Sayre Syndrome / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008715:Methionine; D008875:Middle Aged; D008931:Mitochondria, Muscle / Q000473:pathology* / Q000502:physiology; D008970:Molecular Weight; D009132:Muscles / Q000473:pathology* / Q000503:physiopathology; D009886:Ophthalmoplegia / Q000473:pathology*; D010101:Oxygen Consumption; D014176:Protein Biosynthesis
D003580:Cytochromes; D008715:Methionine