[Regulation of cAMP cascade by yeast RAS genes]

In the yeast, Saccharomyces cerevisiae, cell proliferation is regulated by cAMP through cAMP-dependent protein kinase. Cyclic AMP-dependent phosphorylation is involved in the G1 phase of the cell cycle, conjugation, and the post-meiotic stage of sporulation, but inhibition of cAMP-dependent protein phosphorylation is required in order to induce meiotic division. The yeast RAS gene, which is homologous to the H-ras gene, is one of several genes which are related to cAMP-cascade, and its product seems to be a regulatory protein of adenylate cyclase.