Identification and characterization of MFA1, the gene encoding Candida albicans a-factor pheromone.
In the opaque state, MTLa and MTLalpha strains of Candida albicans are able to mate, and this mating is directed by a pheromone-mediated signaling process. We have used comparisons of genome sequences to identify a C. albicans gene encoding a candidate a-specific mating factor. This gene is conserved in Candida dubliniensis and is similar to a three-gene family in the related fungus Candida parapsilosis but has extremely limited similarity to the Saccharomyces cerevisiae MFA1 (ScMFA1) and ScMFA2 genes. All these genes encode C-terminal CAAX box motifs characteristic of prenylated proteins. The C. albicans gene, designated CaMFA1, is found on chromosome 2 between ORF19.2165 and ORF19.2219. MFA1 encodes an open reading frame of 42 amino acids that is predicted to be processed to a 14-amino-acid prenylated mature pheromone. Microarray analysis shows that MFA1 is poorly expressed in opaque MTLa cells but is induced when the cells are treated with alpha-factor. Disruption of this C. albicans gene blocks the mating of MTLa cells but not MTLalpha cells, while the reintegration of the gene suppresses this cell-type-specific mating defect.
Dignard
Daniel
D
NRC Biotechnology Research Institute, 6100 Royalmount Ave., Montreal, Quebec H4P 2R2, Canada. daniel.dignard@cnrc.gc.ca
El-Naggar
Ahmed L
AL
Logue
Mary E
ME
Butler
Geraldine
G
Whiteway
Malcolm
M
D001483:Base Sequence / Q000235:genetics; D002176:Candida albicans / Q000145:classification / Q000235:genetics*; D015825:Chromosomes, Fungal; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects / Q000502:physiology*; D049770:Genes, Mating Type, Fungal; D016681:Genome, Fungal; D008074:Lipoproteins / Q000235:genetics* / Q000494:pharmacology; D000072235:Mating Factor; D046228:Microarray Analysis; D016366:Open Reading Frames; D010455:Peptides / Q000235:genetics / Q000494:pharmacology; D010675:Pheromones / Q000235:genetics* / Q000494:pharmacology; D011498:Protein Precursors / Q000302:isolation & purification* / Q000378:metabolism*; D017368:Protein Prenylation / Q000235:genetics; D051964:Receptors, Mating Factor / Q000187:drug effects; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology; D016415:Sequence Alignment
D008074:Lipoproteins; C118411:MFA1 protein, S cerevisiae; C095063:MFA2 protein, S cerevisiae; D010455:Peptides; D010675:Pheromones; D011498:Protein Precursors; D051964:Receptors, Mating Factor; D029701:Saccharomyces cerevisiae Proteins; D000072235:Mating Factor