A Candida albicans RAS-related gene (CaRSR1) is involved in budding, cell morphogenesis and hypha development

Microbiology. 1997 Sep;143 ( Pt 9):3033-44. doi: 10.1099/00221287-143-9-3033.


Candida albicans, the most important human fungal pathogen, is a dimorphic fungus that can grow either as a yeast or as a hyphal form in response to medium conditions. A RAS-related C. albicans gene (CaRSR1) was isolated as a suppressor of a cdc24ts bud-emergence mutation of the baker's yeast, Saccharomyces cerevisiae. The deduced protein encoded by CaRSR1 is 248 amino acids long and 56% identical to that encoded by the S. cerevisiae RSR1 (BUD1) gene. Disruption of CaRSR1 in C. albicans indicated that CaRSR1 is involved in both yeast and hypha development. In the yeast phase, CaRSR1 is required for normal (polar) bud site selection and is involved in cell morphogenesis; in the yeast-mycelial transition it is involved in germ tube emergence; and in the development of the hyphae it is involved in cell elongation. The disruption of CaRSR1 leads to reduced virulence in both heterozygote and homozygote disruptants in a dose-dependent manner. The reduced virulence can be attributed to the reduced germination and shorter hyphae resulting from the disruption of CaRSR1.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Candida albicans / genetics*
  • Candida albicans / growth & development*
  • Candida albicans / pathogenicity
  • Cloning, Molecular
  • DNA Primers / genetics
  • DNA, Fungal / genetics
  • GTP Phosphohydrolases / genetics*
  • Genes, Fungal*
  • Genes, Suppressor
  • Humans
  • Molecular Sequence Data
  • Mutation
  • Phenotype
  • Polymerase Chain Reaction
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae Proteins*
  • Sequence Homology, Amino Acid
  • Virulence / genetics
  • rab GTP-Binding Proteins*


  • DNA Primers
  • DNA, Fungal
  • Saccharomyces cerevisiae Proteins
  • GTP Phosphohydrolases
  • RSR1 protein, S cerevisiae
  • rab GTP-Binding Proteins

Associated data

  • GENBANK/U46158