Reduction in GMPs, increase in CMPs, and loss of GCSF response in +42^Mkb enhancer deleted bone marrow. (A) Lineage-negative cKIT⁺Sca-1⁻ (LK) cells were derived from gated c-KIT⁺ cells. The myeloid progenitor cell population including CMP, GMP, and MEP was characterized using CD34 and CD16/32 markers gated from LK cells. (B) Absolute numbers for lineage-negative cells, LK, CMP, and GMP cell populations were calculated from bone marrow white cell count per femur. (C) Cebpa expression measured by RNA-seq expressed as FPKM values derived for WT and homozygous mice in CMP (2wt vs 3hom) and GMP (2wt vs 2hom) sorted fractions. (D) Csf3r expression in total bone marrow by qPCRs, presented as fold change between WT (n = 3) and homozygous (n = 3) mice. RNA-seq analysis of Csf3r in FACS-sorted CMP and GMP cell populations with values expressed as FPKM. (E) Numbers of CSF3-stimulated colonies per 10 000 cells plated obtained from WT bone marrow or from +42^Mkb homozygous deleted mice. Colony numbers represent the average of 3 independent experiments. Representative microphotographs of colonies show differences in sizes and numbers between WT and homozygous mice. FPKM, fragments per kilobase of transcript per million mapped reads.