title: An adenylate cyclase from Saccharomyces cerevisiae that is stimulated by RAS proteins with effector mutations.
abstract: Conservative amino acid substitutions were introduced into the proposed effector regions of both mammalian Ha-ras (residues 32 to 40) and Saccharomyces cerevisiae RAS2 (residues 39 to 47) proteins. The RAS2[Ser 42] protein had reduced biological function in the yeast S. cerevisiae. A S. cerevisiae strain with a second-site suppressor mutation, SSR2-1, was isolated which could grow on nonfermentable carbon sources when the endogenous RAS2 protein was replaced by the RAS2[Ser 42] protein. The SSR2-1 mutation was mapped to the structural gene for adenylate cyclase (CYR1), and the gene containing SSR2-1 was cloned and sequenced. SSR2-1 corresponded to a point mutation that would create an amino acid substitution of a tyrosine residue for an aspartate residue at position 1547. The SSR2-1 gene encodes an adenylate cyclase that is dependent on ras proteins for activity, but is stimulated by Ha-ras and RAS2 mutant proteins that are unable to stimulate wild-type adenylate cyclase.
authors.affiliation: Department of Virus and Cell Biology, Merck Sharp & Dohme Research Laboratories, West Point, Pennsylvania 19486.
authors.forename: M S
authors.initials: MS
authors.lastname: Marshall
authors.forename: J B
authors.initials: JB
authors.lastname: Gibbs
authors.forename: E M
authors.initials: EM
authors.lastname: Scolnick
authors.forename: I S
authors.initials: IS
authors.lastname: Sigal
mesh_terms: D000262:Adenylyl Cyclases / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004252:DNA Mutational Analysis; D011905:Genes, ras; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013329:Structure-Activity Relationship; D013489:Suppression, Genetic
chemical_list: D011518:Proto-Oncogene Proteins; D000262:Adenylyl Cyclases