Parameters for simulations of budding yeast.

Exposure to mating pheromone of haploid Saccharomyces cerevisiae cells results in polarized growth towards the mating partner. Proteins involved in signaling, polarization, cell adhesion, and fusion are localized at the tip of the mating cell (shmoo) where fusion will eventually occur. Polarization involves localization of the small GTPase Cdc42 and of its guanine nucleotide exchange factor (GEF), Cdc24. The expression of a constitutively activated form of Cdc42 is sufficient to cause polarization in otherwise nonpolarized cells.