HSC-specific expression of Srsf2^P95H/+causes myeloid bias. (A) Experimental outline and timeline. (B) PB indices over 20 weeks after Cre activation. (C) PB leukocyte counts and lineage distribution at 20 weeks after Cre activation (n = 7-23 per genotype per time point). (D) PB eYFP levels over time (n = 7-23 per genotype per time point). (E) Histograms of CD45RB isoform expression on splenocytes of the indicated genotypes (n = 4^+/+; n = 5 P95H^/+). (F) BM cellularity per femur. (G) Number and frequency of granulocytes and monocytes per femur. (H) Number of B cells and B-cell progenitor populations per femur. (I) Erythroid populations per femur. Number of phenotypic LT-HSC, ST-HSC, and MPP populations per femur using the (J) lin⁻cKit⁺Sca1⁺CD34/Flt3 or lin⁻cKit⁺Sca1⁺CD105/CD150 (K) phenotype. (L) Numbers of myeloerythroid progenitors per femur. (F-K) n = 7^+/+; n = 8 P95H^/+. Presented as mean ± standard error of the mean. Student t test. *P < .05, **P < .01, ***P < .001. CFU-E, colony-forming unit erythroid; GMP, granulocyte macrophage progenitor; IgM, immunoglobulin M; MkP, megakaryocyte progenitor; preMegE, premegakaryocyte erythroid progenitor.