cAMP-dependent phosphoprotein changes in the yeastSaccharomyces cerevisiae

cAMP-dependent phosphoprotein changes were determined using 1-dimensional SDS-gel electrophoresis in a cAMP-requiring yeast mutant (Saccharomyces cerevisiae AM18). During cAMP starvation, the yeast cells accumulated 3 32P-labeled bands with Mr/ 72000, 54000, and 37000. The Mr/ 72000 protein was the most prominent phosphorylated protein. After the readdition of cAMP, these phosphoproteins lost their 32P-label while phosphoproteins with Mr/ 76000, 65000, 56000 and 30000 were accumulated. Similar phosphoprotein changes were also detected in cdc35 at the nonpermissive temperature, but not in wildtype (A363A) or cdc7 strains of S. cerevisiae.