The growth of mdp1/rsp5 mutants of Saccharomyces cerevisiae is affected by mutations in the ATP-binding domain of the plasma membrane H+ -ATPase.
Mutations in the PMA1 gene, encoding plasma membrane H+ -ATPase, were isolated that are able to suppress the temperature sensitivity (ts) phenotype of mdp1 mutations located in RSP5, the ubiquitin-protein ligase gene. The mdp1 mutants were previously found to change the mitochondrial/cytosolic distribution of Mod5p-I, the tRNA modifying enzyme, and to affect fluid phase endocytosis. The data presented reveal that mdp1 mutants are also pH sensitive, and hypersensitive to hygromycin B and paromomycin. The ts phenotype, hygromycin B and paromomycin sensitivity are suppressed by pmal-t, but the pH sensitivity, the effect of mdp1 on Mod5p-I cytoplasmic/mitochondrial localization and endocytosis are not. Characterization of pmal-t revealed the substitution of amino acid G(653)V in the ATP-binding domain of the H+ -ATPase. Our results indicate that Rsp5 ubiquitin-protein ligase may also influence, in addition to protein distribution, the functioning of plasma membrane H+ -ATPase and the response of cells to stress.
Kamińska
J
J
Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw.
Tobiasz
A
A
Gniewosz
M
M
Zoładek
T
T
D000255:Adenosine Triphosphate / Q000378:metabolism; D019883:Alkyl and Aryl Transferases; D001665:Binding Sites / Q000235:genetics; D002455:Cell Division / Q000235:genetics; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000235:genetics / Q000302:isolation & purification; D004272:DNA, Mitochondrial / Q000235:genetics; D004705:Endocytosis / Q000235:genetics; D056827:Endosomal Sorting Complexes Required for Transport; D005656:Fungal Proteins / Q000235:genetics* / Q000502:physiology; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D006921:Hygromycin B / Q000494:pharmacology; D008928:Mitochondria / Q000201:enzymology; D009154:Mutation; D010303:Paromomycin / Q000494:pharmacology; D011506:Proteins / Q000378:metabolism; D006180:Proton-Translocating ATPases / Q000235:genetics* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins; D043743:Ubiquitin-Protein Ligase Complexes
D004271:DNA, Fungal; D004272:DNA, Mitochondrial; D056827:Endosomal Sorting Complexes Required for Transport; D005656:Fungal Proteins; C434364:PMA2 protein, S cerevisiae; D011506:Proteins; D029701:Saccharomyces cerevisiae Proteins; D006921:Hygromycin B; D010303:Paromomycin; D000255:Adenosine Triphosphate; D043743:Ubiquitin-Protein Ligase Complexes; D019883:Alkyl and Aryl Transferases; C068392:MOD5 protein, S cerevisiae; C092477:PMA1 protein, S cerevisiae; D006180:Proton-Translocating ATPases; C469287:RSP5 protein, S cerevisiae