MCL-1 is expressed in early erythropoiesis. (A-B) Mouse fetal livers were isolated from E12.5 embryos and mechanically dissociated. Fetal liver cells were labeled with CD45, CD71, and TER119 antibodies. Following CD45⁻ gating, cells were sorted 4 ways using a FACSAria; S1 and S2 were combined because of low cell number. (A) Quantitative PCR was performed on sorted populations for the indicated anti- or proapoptotic family members. Expression is represented as fold change relative to housekeeping gene (Ubc). n = 12 embryos from 3 litters, bars represent mean ± standard error of the mean. *P < .05, **P < .1, ***P < .01, vs S0 with α = 0.05, 1-way analysis of variance (ANOVA). (B) Cells were lysed in RIPA buffer containing phosphatase inhibitor cocktail and then immunoblot was performed on sorted cell populations. Wild-type murine embryonic fibroblast (MEF) lysates are included as positive control where indicated. (C-D) Fetal liver cells were isolated from E12.5 wild-type embryos; TER119⁻ progenitor cells were purified using MACS MicroBeads and then cultured on fibronectin-coated plates for the indicated time points without (Unstim) or with 2 U/mL human EPO (+EPO). (C) Quantitative PCR was performed for the indicated anti- or proapoptotic family members. Expression is represented as fold change relative to housekeeping gene (Ubc); n = 12 embryos from 3 litters. *P < .05, 1-way ANOVA with α = 0.05, where indicated. (D) Immunoblot was performed to detect the indicated proteins. ns, not significant.