KLF7 suppression of HSPC function is not mediated by CDKN1A. (A) Cdkn1a mRNA expression relative to β-actin in GFP⁺ KLS cells 72 hours after transduction with lentivirus expressing KLF7 or vector alone. (B) Bone marrow cells exposed to KLF7 or control lentivirus were plated in methylcellulose and colonies scored on day 7. The percentage of GFP⁺ colonies is shown, normalized for the transduction efficiency. Data represent 2 independent experiments, plated in duplicate. *P = .0002. Cdkn1a^−/− bone marrow was transduced with KLF7 or control lentivirus and transplanted into irradiated congenic recipients. Six weeks after transplantation, the percentage of donor leukocytes (C), cells of the indicated hematopoietic lineage (D), or indicated progenitor cell population (E) that was GFP⁺ was determined. Time zero in panel C refers to the transduction efficiency. Input indicates the percentage of GFP⁺ cells at the time of transplantation. Data represent 2 individual experiments, each with 5 or 6 mice per genotype. *P < .01. **P < .05. ***P < .0001.