FIG. 1.

(A) Fluorescence-activated cell sorting analysis of E13.5 fetal liver cells from wild-type and Eklf^−/− embryos. The cells were stained with anti-CD71 (transferrin receptor; y axis) and TER119 (x axis) antibodies. The sorting windows for the R1-R5 populations are indicated by the labeled ovals. (B) Morphology of representative Wright-Giemsa-stained cells in the sorted R1-R5 populations. Wild-type R1 was composed of 98% large blast cells and 2% other cells, wild-type R2 was composed of 99% smaller blast cells and 1% other cells, wild-type R3 was composed of 99% smaller hemoglobin-staining cells with compacted nuclei and 1% other cells, wild-type R4 was composed of 99% cells with dark hemoglobin staining and decentralized nuclei and 1% other cells, and wild-type R5 was composed of 99% reticulocytes and 1% other cells. Eklf^−/− R1 was composed of 97.5% large blast cells and 2.5% other cells, while Eklf^−/− R2 was composed of 97% smaller blast cells and 3% other cells. WT, wild type.