Alpha-factor enhancement of hybrid formation by protoplast fusion in the yeast Saccharomyces cerevisiae.

Two a strains of Saccharomyces cerevisiae, carrying complementary genetic markers, were arrested for 3 h with alpha-factor. These were then protoplasted, prior to fusion using polyethylene glycol. The number of viable fusion products was enhanced by a factor of 20 as compared with unarrested controls.