Disruption of stem cell quiescence and DNA replication dynamics by concurrent Hoxa9/β-catenin deletion. (A) Representative fluorescence-activated cell sorting plots of Ki67 and Hoechst 33342 staining of LSKs isolated from indicated mice. (B) Percentage of LSKs in G0 cell cycle phase. Percentage Ki67+ (C) and BrdU+ (D) LSKs (n = 3 mice per group). (E) CldU track length of DNA fibers from HSPCs isolated from indicated mice. (F) Representative images of replication fork lengths. Scale bar, 10 μm. (G) Ratio of IdU track lengths of bidirectional forks. (H) Percentage of stalled forks (green only) present in single/combined KO cells. Fiber data from 1 representative experiment is shown (n = 3; data is shown in supplemental Figure 2). Immunofluorescent images (I) and focus counts (J) of ƳH2AX staining on HSPCs isolated from indicated mice. Several fields of cells were scored from 2 independent experiments. Scale bars, 25 μm. WT BL6 mice treated with corn oil (vehicle) are indicated as WT control. ∗P ≤ .05; ∗∗P ≤ .01; ∗∗∗P ≤ .001; ∗∗∗∗P ≤ .0001; NS, P > .05.
