The interspacing sequences between the 3 cis-elements in the GdC-region are required for the inactivation of Gata1 gene expression in HSCs. (A) GFP and c-Kit expression profiles in the bone marrow cells of the G1B-GFP (line 392) and MG-GFP (line 20) mice. (B) Percentages of the GFP-positive fraction within the c-Kit−positive progenitors in the MG-GFP line 19 (n = 5), line 20 (n = 4), and G1B-GFP line 392 (n = 9) transgenic mice. (C) The relative mean GFP intensity in the c-Kit−positive or c-Kit−negative fraction of the MG-GFP line 19 (n = 8), line 20 (n = 8), and G1B-GFP line 392 (n = 10) transgenic mice. (D) The relative GFP intensity during erythroid cell differentiation in the MG-GFP lines 19 (n = 4), line 20 (n = 4), and in the G1B-GFP line 392 (n = 6) transgenic mice. The X-axis indicates each stage of erythroid cell differentiation. LSK: Lin−Sca1+c-Kit+, fraction-containing HSCs, CMPs, MEPs, colony-forming unit-erythroid (CFU-E) stage cells, ProEB, basophilic erythroblast (Baso), and polychromatic erythroblast (Poly). (E) GFP mRNA expression analyzed by qRT-PCR in the LSK fraction (n = 9) or basophilic EB fraction (n = 6). The qRT-PCR results are normalized according to the glyceraldehydes-3-phosphate dehydrogenase level. (F) GFP histogram of the LSKS (Lin−Sca1+c-Kit+CD150+CD48−) fraction. The depicted histogram is from a representative experiment that was repeated more than 3 times. Data are presented as the mean ± SD. The statistical significance of differences is indicated (***P < .001; **P < .01; n.s., not significant; Student unpaired t test).