Knockout of Aurka leads to a striking reduction in myeloid progenitors. (A) Colony forming assays of bone marrow cells 14 days after pI-pC treatment from control (WT) or Aurka^fl/fl/Mx1-Cre (Aurka^−/−) mice; 25 000 and 100 000 cells were plated for the burst forming unit-erythroid (BFU-E), CFU-M, and CFU-MK assays. Colonies were enumerated 7 to 10 days after plating. Data are shown as mean ± SD. (B) Flow cytometry analysis of myeloid and megakaryocyte progenitors in the bone marrow. Means + SD of the different populations in WT vs Aurka^−/− mice analyzed 6 days after the first pI-pC treatment are shown; n = 2. Progenitor counts were normalized per 10 000 bone marrow cells. *P < .05; **P < .01. Representative FACS plots are shown in supplemental Figure 1.