Effects of several inhibitors on the cell death of adult-type RBCs induced by xTRAIL1, and the expression of PKC isoforms during development, including metamorphosis. (A) RBCs Isolated from adult frogs were pretreated with staurosporine (50nM), bisindolylmaleimide I (20μM), wortmannin (10μM), PD98059 (10μM), or ET-18-OCH3 (10 μg/mL) for 1 hour and then treated with cross-linked xTRAIL1 (5, 25, 50 ng/mL). After 24 hours, the cell viability was measured and shown as described in Figure 5. The data represent the mean (n = 4) and SD; *P < .01. (B) The expression of PKCα and xPKCϵ mRNAs from stage 55 to adult was analyzed by real-time RT-PCR. The cDNAs were amplified by PCR using gene-specific primer pairs (see Table 1). The copy number of each PKC was normalized to that of EF1α and is shown as the percentage of the value obtained in adult RBCs. The data represent the mean (n = 3) and SD; *P < .05 and **P < .001 compared with stage 55.
