Analysis of BL-CFC potential ofRunx1^+/+, Runx1^+/−, and Runx1^−/− EBs.

(A) Number of blast colonies generated by day 3.5 and 4Runx1^+/+ (+/+), Runx1^+/−(+/−), and Runx1^−/− (−/−) EB-derived cells. Two Runx1^−/− clones (−/−A, −/−B) were analyzed. Bars represent standard error of the mean number of colonies from at least 3 cultures. (B) Rescue of the BL-CFC potential ofRunx1^−/− ES cells.Runx1^−/− ES cells infected with either a retrovirus expressing the Runx1b isoform of the gene (MSCVRunx1) or with an empty virus control (MSCV) and selected with puromycin were differentiated for the indicated periods of time. EBs were harvested and analyzed for BL-CFCs. Bars represent standard error of the mean number of colonies from at least 3 cultures.