MG-G1 BAC transgenic mice exhibit enhanced erythropoiesis and HSPC depletion during the embryonic stage. (A) Fetal liver cellularity in E13.5, E14.5, and E17.5 embryos. Note that MG-G1 fetal livers showed a significant reduction in the hematopoietic cell population compared to that in wild-type fetal livers. (B) Percentages of LSK cells in E13.5, E14.5, and E17.5 fetal livers of MG-G1 and littermate control embryos. (C and D) Flow cytometry analysis of LSK cell (C) and progenitor (D) fractions. (E) CMP, GMP, and MEP percentages in E17.5 fetal livers of MG-G1 and littermate control embryos. (F) Flow cytometry analysis of proerythroblasts from WT and MG-G1 E17.5 fetal livers. (G) Percentages of CD71+ Ter119+ proerythroblasts in E17.5 livers. (H) Flow cytometry analysis of Mac1/Gr1+ and B220+ cells from WT and MG-G1 E14.5 fetal livers. (I) Percentages of Mac1/Gr1+ and B220+ cells. Data shown are the means ± SD for three to six mice. *, P < 0.05; **, P < 0.01; ***, P < 0.001 (unpaired Student's t test). N.S., not significant.