Runx1 is required for the maintenance of the AMP population. (A-D) The indicated groups of mice were treated with pIpC to induce the expression of Cbfb-MYH11 and/or Runx1 deficiency. At certain time points after pIpC treatment, the mice were killed, and flow cytometry assays were performed. (A) Representative FACS plots of bone marrow cells from mice treated with pIpC for 2 to 3 weeks gated on single cells (i), Lin⁻ cells (ii), and LK cells (iii) are shown for the intensities of the indicated antibodies. (B) Bar graphs showing the percentages (mean ± SEM) of Lin⁻ of bone marrow and LK fraction of Lin⁻ compartments in mice of the indicated genotypes as showed in panel A. (C) Representative FACS plots of bone marrow cells gated on LK cells from mice treated with pIpC for 4 to 5 weeks and 4 months. (D) Bar graph showing the percentages (mean ± SEM) of the AMP population in the bone marrow of mice of indicated genotypes treated with pIpC for 2 to 3 weeks, 4 to 5 weeks, and 4 months as showed in panels A and C. *P < .05, **P < .01, ***P < .001, ****P < .0001. All genotypes in this figure are color-coded the same way (blue for Mx1-CreCbfb^+/56M, red for Runx1^f/fMx1-CreCbfb^+/56M, and green for Runx1^f/fMx1-Cre).