Deletion of p53 in addition to NF-Ya does not rescue the defects of NF-Ya–deficient BM cells and HSCs. (A) Protein from wt and p53 conditional ko BM 7 days after pIpC treatment was subjected to Western blot analysis and probed with a p53 (top) and actin (bottom) Ab. (B) Representative flow cytometric staining of control (left) and NF-Ya ko (right) for TUNEL and PI. Note, NF-Ya sko and NF-Ya, p53 dko (not shown) stainings are indistinguishable. (C) Results from panel B are summarized in this bar graph (n = 5); **P < .01. (D) CD45.1⁺ recipients received a BM transplant from NF-Ya^+/++Mx-cre (control), NF-Ya^fl/fl+Mx-cre (ko), and NF-Ya^fl/fl, p53^fl/fl+Mx-cre (dko), (all CD45.2⁺) mice together with 30% CD45.1⁺ NF-Ya wt competitor cells. The mice were treated with pIpC at day 0. The CD45.1-to-CD45.2 ratio of PB cells was determined and normalized to day 0 (n = 8 [control], n = 7 [sko], n = 6 [(dko]). (E) Mice from panel D were killed, and the indicated BM subpopulations were analyzed for CD45.1 versus CD45.2 expression and are shown in a bar graph; control (gray) and ko (black).