Caspase-3 inhibits growth in Saccharomyces cerevisiae without causing celldeath

Caspase-3, a member of the caspase family of cell death proteases, cleaves cytoplasmic and nuclear substrates and promotes apoptotic cell death in mam malian cells. Although yeast homologs of apoptotic genes have not been iden tified, some components of apoptotic pathways retain function in yeast. Her e we show that the expression of caspase-3 delays cell growth in Saccharomy ces cerevesiae without causing cell death. Mutation of the caspase-3 QACRG active site abolished effects on yeast growth. Go-expression of caspase inh ibitors alleviated growth inhibition in yeast as did the tripeptide caspase inhibitor ZVAD-fmk, These results suggest that substrates for caspase-3 ar e present in S, cerevesiae and may participate in the normal cell growth an d division processes. (C) 1999 Federation of European Biochemical Societies .