Multicopy suppression screen in a Saccharomyces cerevisiae strain lacking the Rab GTPase-activating protein Msb3p.
The yeast proteins, Msb3p and Msb4p, are two Ypt/Rab-specific GTPase-activating proteins sharing redundant functions in exocytosis, organization of the actin cytoskeleton, and budding site selection. To see if Msb3p might play an additional, specific role, we first tested the sensitivities of msb3 and msb4 mutant strains to different drugs and then screened a genomic library for multicopy suppressors of msb3 sensitivity to CdCl(2) or to the calcium channel blocker diltiazem hydrochloride. Three genes (ADH1, RNT1, and SUI1) were found to suppress the CdCl(2) sensitivity of the msb3 strain and three others (YAP6, ZEO1, and SLM1) its diltiazem-HCl sensitivity. The results suggest a possible involvement of Msb3p in calcineurin-mediated signalling.
Biver
Sophie
S
Unité de Biologie Animale et Microbienne, Gembloux Agro-Bio Tech, Université de Liège, Avenue Maréchal Juin 6, 5030, Gembloux, Belgium. Sophie.Biver@ulg.ac.be
Portetelle
Daniel
D
Vandenbol
Micheline
M
D000935:Antifungal Agents / Q000494:pharmacology; D019256:Cadmium Chloride / Q000494:pharmacology; D004110:Diltiazem / Q000494:pharmacology; D020690:GTPase-Activating Proteins / Q000172:deficiency* / Q000378:metabolism*; D005800:Genes, Fungal; D005827:Genetics, Microbial / Q000379:methods; D008403:Mass Screening / Q000379:methods; D008826:Microbial Sensitivity Tests; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D013489:Suppression, Genetic; D020691:rab GTP-Binding Proteins / Q000378:metabolism*
D000935:Antifungal Agents; D020690:GTPase-Activating Proteins; C540987:MSB3 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D020691:rab GTP-Binding Proteins; D004110:Diltiazem; D019256:Cadmium Chloride