Bag1 deficiency inhibits maturation of erythroblasts in vivo. (A) Total number of nucleated cells in E12.5 fetal livers from Bag1^+/+, Bag1^+/−, and Bag1^−/− embryos. *P < .001. (B) Number of colonies in BFU-E and CFU-GM assays represented as colonies per cell from E12.5 fetal livers, as in panel A. *P < .001. (C-D) FACS analysis of the 7AAD⁻ cells from fetal livers, as in panel A. The gated area represents the Ter119⁻ cells, which are quantified as the percentage of the total in the graph in panel D. *P < .005.