The a-factor pheromone of Saccharomyces cerevisiae is essential for mating.

AUTOR(ES)

Michaelis, S

RESUMO

The Saccharomyces cerevisiae pheromone a-factor is produced by a cells and interacts with alpha cells to cause cell cycle arrest and other physiological responses associated with mating. Two a-factor structural genes, MFA1 and MFA2, have been previously cloned with synthetic probes based on the a-factor amino acid sequence (A. Brake, C. Brenner, R. Najarian, P. Laybourn, and J. Merryweather, cited in M.-J. Gething [ed.], Protein transport and secretion, 1985). We have examined the function of these genes in a-factor production and mating by construction and analysis of chromosomal null mutations. mfa1 and mfa2 single mutants each exhibited approximately half the wild-type level of a-factor activity and were proficient in mating, whereas the mfa1 mfa2 double mutant produced no a-factor and was unable to mate. These results demonstrate that both genes are functional, that each gene makes an equivalent contribution to the a-factor activity and mating capacity of a cells, and that a-factor plays an essential role in mating. Strikingly, exogenous a-factor did not alleviate the mating defect of the double mutant, suggesting that an a cell must be producing a-factor to be an effective mating partner.

Documentos Relacionados

• Significance of C-terminal cysteine modifications to the biological activity of the Saccharomyces cerevisiae a-factor mating pheromone.
• a-Factor from Saccharomyces cerevisiae: partial characterization of a mating hormone produced by cells of mating type a.
• a-Factor from Saccharomyces cerevisiae: Partial Characterization of a Mating Hormone Produced by Cells of Mating Type a
• A Homolog of Ste6, the a-Factor Transporter in Saccharomyces cerevisiae, Is Required for Mating but Not for Monokaryotic Fruiting in Cryptococcus neoformans
• SPT3 is required for normal levels of a-factor and alpha-factor expression in Saccharomyces cerevisiae.