Fig. 4. Expression of Bcl-xL abrogates S. cerevisiae acetic-acid-induced apoptosis. Co-expression of mammalian PKC-, -, - or - differently modulate Bcl-xL effects in S. cerevisiae acetic-acid-induced apoptosis. Yeast co-transformed with the empty vectors, pOW4 and YEp51 or pOW4 and YEplac181 (black), expressing Bcl-xL (pale grey) and co-expressing Bcl-xL and PKC-, -, - or - (dark grey) were incubated with acetic acid for 1 hour at 30°C. (A) Cell death experiments. Percentage of dead cells was determined by c.f.u. counts as in Fig. 1. Data are the mean ± s.e.m. of three independent experiments with six replicates. (B) TUNEL staining. Cells treated in the absence of acetic acid (0 mM) were used as negative control. Data are the mean ± s.e.m. of two independent experiments; means correspond to counts of at least 600 cells per sample. Significantly differences from those obtained with yeast co-transformed with the empty vectors and with yeast only expressing Bcl-xL are indicated by ^*P<0.05 and ^#P<0.05 (unpaired Student's t-test), respectively.