SST2, a regulator of G-protein signaling for the Candida albicans mating response pathway.
Candida albicans contains a functional mating response pathway that is similar to the well-studied system of Saccharomyces cerevisiae. We have characterized a regulator of G protein signaling (RGS) homolog in C. albicans with sequence similarity to the SST2 gene of Saccharomyces cerevisiae. Disruption of this gene, which had been designated SST2, causes an opaque MTLa/MTLa derivative of strain SC5314 to show hypersensitivity to the C. albicans alpha-factor. This hypersensitivity generates an enhanced cell cycle arrest detected in halo assays but reduces the overall mating efficiency of the cells. Transcriptional profiling of the pheromone-regulated gene expression in the sst2 mutant shows a pattern of gene induction similar to that observed in wild-type cells, but the responsiveness is heightened. This involvement of an RGS in the sensitivity to pheromone is consistent with the prediction that the mating response pathway in C. albicans requires the activation of a heterotrimeric G protein.
Dignard
Daniel
D
Genetics Group, Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Ave., Montreal, Quebec H4P 2R2, Canada.
Whiteway
Malcolm
M
D002176:Candida albicans / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D005800:Genes, Fungal; D049770:Genes, Mating Type, Fungal / Q000502:physiology*; D016681:Genome, Fungal; D000072235:Mating Factor; D020411:Oligonucleotide Array Sequence Analysis; D010455:Peptides / Q000494:pharmacology; D020710:RGS Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
D005656:Fungal Proteins; D010455:Peptides; D020710:RGS Proteins; D000072235:Mating Factor