Open AccessBiogenesis of mitochondria: DNA sequence analysis ofmit−mutations in the mitochondrialoli2gene coding for mitochondrial ATPase subunit 6 inSaccharomyces cerevisiae
Author(s) -
Ulrik P. John,
Tracy A. Willson,
Anthony W. Linnane,
Phillip Nagley
Publication year - 1986
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/14.18.7437
Subject(s) - biology , frameshift mutation , protein subunit , mutant , gene , microbiology and biotechnology , amino acid , scn3a , mitochondrial dna , mutagenesis , biochemistry , genetics , mutation , g alpha subunit
A series of yeast mitochondrial mit- mutants with defects in the oli2 gene, coding for subunit 6 of the mitochondrial ATPase complex, has been analyzed at the DNA sequence level. Fifteen of sixteen primary mit- mutants were shown to contain frameshift or nonsense mutations predicting truncated subunit 6 polypeptides, in various strains ranging from about 20% to 95% of the wild-type length of 259 amino acids. In only one strain could the defect in subunit 6 function be assigned to amino acid substitution in an otherwise full-length subunit 6. Many mutants carried multiple base substitutions or insertions/deletions, presumably arising from the manganese chloride mutagenesis treatment. Revertants from three of the mit- mutants were analyzed: all contained full-length subunit 6 proteins with one or more amino acid substitutions. The preponderance of truncated proteins as opposed to substituted full-length proteins in oli2 mit- mutants is suggested to reflect the ability of subunit 6 to accommodate amino acid substitutions at many locations, with little or no change in its functional properties in the membrane FO-sector of the ATPase complex.