YCA1 participates in the acetic acid induced yeast programmed cell death also in a manner unrelated to its caspase-like activity

Yeast cells lacking the metacaspase-encoding gene YCA1 (Delta yca1) were compared with wild-type (WT) cells with respect to the occurrence, nature and time course of acetic-acid triggered death. We show that Delta yca1 cells undergo programmed cell death (PCD) with a rate lower than that of the WT and that PCD in WT cells is caused at least in part by the caspase activity of Yca1p. Since in Delta yca1 cells this effect is lost, but z-VAD-fmk does not prevent both WT and Delta yca1 cell death, PCD in WT cells occurs via a Yca1p caspase and a non-caspase route with similar characteristics. (c) 2006 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.