title: Farnesylation of YDJ1p is required for function at elevated growth temperatures in Saccharomyces cerevisiae.
abstract: The Saccharomyces cerevisiae YDJ1 protein (YDJ1p) contains a C-terminal "CaaX box" motif common to proteins that are modified by prenylation. In the present study we show that YDJ1p is a specific substrate for both yeast and mammalian protein farnesyltransferase enzymes in vitro. A mutant form of YDJ1p, in which the conserved cysteine of the CaaX box is mutated to a serine (ydj1-S406p), cannot be farnesylated in vitro. After expression in S. cerevisiae, ydj1-S406p displays a reduced electrophoretic mobility and an increased cytosolic localization in subcellular fractionation experiments when compared to wild type YDJ1p. Expression of ydj1-S406 in cells lacking YDJ1 results in a temperature-sensitive growth phenotype in S. cerevisiae. These data indicate that farnesylation of YDJ1p is required for its function at elevated temperatures.
authors.affiliation: Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill 27599.
authors.forename: A J
authors.initials: AJ
authors.lastname: Caplan
authors.forename: J
authors.initials: J
authors.lastname: Tsai
authors.forename: P J
authors.initials: PJ
authors.lastname: Casey
authors.forename: M G
authors.initials: MG
authors.lastname: Douglas
mesh_terms: D019883:Alkyl and Aryl Transferases; D004591:Electrophoresis, Polyacrylamide Gel; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D006358:Hot Temperature; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000254:growth & development* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity; D014166:Transferases / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D029701:Saccharomyces cerevisiae Proteins; C070319:YDJ1 protein, S cerevisiae; D014166:Transferases; D019883:Alkyl and Aryl Transferases; C064911:p21(ras) farnesyl-protein transferase