(A) Deletion of Trp53 rescues postnatal death by Rps27l disruption. Lower than expected number of mice with Trp53−/− genotype (regardless of Rps27l genotype) is due to high frequency of developmental abnormalities during embryonic and neonatal stages which cause the premature death (Armstrong et al., 1995; Sah et al., 1995). (B–D) Deletion of Trp53 rescues growth retardation and organ hypocellularity. Representative mice at P18 of three genotypes were photographed (B). The bodies (C) were weighed; and the total cell numbers (D) of bone marrow (femur and tibia from two hind limbs), spleen, and thymus were counted from P18 mice with genotypes of Rps27l+/+;Trp53+/+ (n = 3), Rps27l−/−;Trp53+/+ (n = 7), Rps27l−/−-;Trp53+/− (n = 10), Rps27l−/−;Trp53−/− (n = 5). Shown are mean ± SD. *p < 0.05, **p < 0.01, and ***p < 0.001. (E) Representative H&E staining of bone marrows in femurs from P18 mice. Scale bars represent 200 µm (top) or 40 µm (bottom). (F and G) Deletion of Trp53 rescues HSPCs depletion in Rps27l−/− bone marrow. The percentage of LSK, MPP, ST-HSC, and LT-HSC (F); and the percentage of MP, CMP, GMP, and MEP (G) in bone marrow from P18 mice with genotypes of Rps27l+/+;Trp53+/+ (n = 4), Rps27l−/−;Trp53+/+ (n = 5), Rps27l−/−;Trp53+/− (n = 7), and Rps27l−/−;Trp53−/− (n = 5). LSK: Lin−/Sca-1−/c-Kit+; MPP: Lin−/Sca-1−/c-Kit+/CD48+/CD150−; ST-HSC: Lin−/Sca-1−/c-Kit+/CD48+/CD150+; LT-HSC: Lin−/Sca-1−/c-Kit+/CD48−/CD150+. Shown are mean ± SD. *p < 0.05, **p < 0.01, and ***p < 0.001. (H) Deletion of Trp53 rescues defects in Rps27l−/− peripheral blood. CBC classification of peripheral blood from Rps27l+/+;Trp53+/+ (n = 3), Rps27l−/−;Trp53+/+ (n = 7), Rps27l−/−;Trp53+/− (n = 10), Rps27l−/−;Trp53−/− (n = 5) mice at P18 was performed. WBC, white blood cells; NE, neutrophils; LY, lymphocytes; MO, monocytes; HCT, hematocrit; RBC, red blood cells; Hb, hemoglobin; PLT, platelets. Shown are mean ± SD. *p < 0.05, **p < 0.01, and ***p < 0.001. (I and J) Deletion of Trp53 rescues HSPCs depletion in Rps27l−/− fetal livers. Flow cytometry analysis was performed to measure the percentage of HSPCs including LSK (I), MP, CMP, GMP, and MEP (J) in E14.5 fetal livers with genotypes of Rps27l−/−;Trp53+/+ (n = 5), Rps27l−/−;Trp53+/− (n = 7), and Rps27l−/−;Trp53−/− (n = 6). Shown are mean ± SD. *p < 0.05, **p < 0.01, and ***p < 0.001, as compared to Rps27l−/−;Trp53+/+. (K) Kaplan–Meier survival curves of recipient mice after transplantation. Fetal liver cells (2 × 106 cells) from E14.5 embryos with indicated genotypes were respectively injected into lethally irradiated recipient mice (n = 7 for each genotype). p < 0.0001.
DOI:
http://dx.doi.org/10.7554/eLife.02236.015