The Candida albicans CaACE2 gene affects morphogenesis, adherence and virulence.
Morphogenesis between yeast and hyphal growth is a characteristic associated with virulence in Candida albicans and involves changes in the cell wall. In Saccharomyces cerevisiae, the transcription factor pair Ace2p and Swi5p are key regulators of cell wall metabolism. Here, we have characterized the CaACE2 gene, which encodes the only C. albicans homologue of S. cerevisiae ACE2 and SWI5. Deleting CaACE2 results in a defect in cell separation, increased invasion of solid agar medium and inappropriate pseudohyphal growth, even in the absence of external inducers. The mutant cells have reduced adherence to plastic surfaces and generate biofilms with distinctly different morphology from wild-type cells. They are also avirulent in a mouse model. Deleting CaACE2 has no effect on expression of the chitinase gene CHT2, but expression of CHT3 and the putative cell wall genes CaDSE1 and CaSCW11 is reduced in both yeast and hyphal forms. The CaAce2 protein is localized to the daughter nucleus of large budded cells at the end of mitosis. C. albicans Ace2p therefore plays a major role in morphogenesis and adherence and resembles S. cerevisiae Ace2p in function.
Kelly
Mary T
MT
Department of Biochemistry, Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland.
MacCallum
Donna M
DM
Clancy
Susanne D
SD
Odds
Frank C
FC
Brown
Alistair J P
AJ
Butler
Geraldine
G
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018441:Biofilms; D002176:Candida albicans / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity; D002177:Candidiasis / Q000473:pathology; D002448:Cell Adhesion; D003001:Cloning, Molecular; D017124:Conserved Sequence; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics*; D004195:Disease Models, Animal; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics; D007668:Kidney / Q000382:microbiology / Q000473:pathology; D007700:Kinetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics*; D016415:Sequence Alignment; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics*; D014774:Virulence / Q000235:genetics
C066778:ACE2 protein, S cerevisiae; D017931:DNA Primers; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors