The NAM9-1 suppressor mutation in a nuclear gene encoding ribosomal mitochondrial protein of Saccharomyces cerevisiae.
The nuclear gene NAM9 from Saccharomyces cerevisiae (Sc) codes for a protein which, on the basis of sequence homology, was previously postulated to be a mitochondrial (mt) equivalent of the Escherichia coli (Ec) S4 ribosomal protein (r-protein) [Boguta et al., Mol. Cell. Biol. 12 (1992) 402-412]. The mt-r character of the NAM9 product is now confirmed by cross-reaction with the antisera for the Sc mt r-proteins. The NAM9-1 mutation, characterized previously as the nuclear suppressor of some ochre mt mit- mutants, is found to be a single nucleotide substitution changing Ser82 to Leu within the part of NAM9 corresponding to the S4 region involved in interaction with the 16S rRNA. This indicates that the mechanism of NAM9-1 suppression could be analogous to the suppression due to ram (ribosomal ambiguity) mutations in the Ec structural gene encoding r-protein S4. The NAM9-1 mutation leads also to defect in respiratory growth in the background of the wild-type mit+ genome.
Dmochowska
A
A
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw.
Konopińska
A
A
Krzymowska
M
M
Szcześniak
B
B
Boguta
M
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D002451:Cell Compartmentation; D002467:Cell Nucleus / Q000235:genetics*; D003429:Cross Reactions; D005656:Fungal Proteins / Q000235:genetics* / Q000276:immunology; D005800:Genes, Fungal; D008928:Mitochondria / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins; D012097:Repressor Proteins; D012269:Ribosomal Proteins / Q000235:genetics* / Q000276:immunology; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D013489:Suppression, Genetic
D005656:Fungal Proteins; C072080:NAM9 protein, S cerevisiae; D009687:Nuclear Proteins; D012097:Repressor Proteins; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; C031798:ribosomal protein S4