Growth factor independence 1b (Gfi1b) is required for erythroid cell maturation and regulates embryonic globin expression [MoGene-1_0]

Growth factor independence 1b (Gfi1b) is a DNA binding repressor of transcription with vital functions in hematopoiesis. Gfi1b-null embryos die at midgestation very likely due to defects in erythro- and megakaryopoiesis. To analyze the full functionality of Gfi1b in embryonic erythropoiesis, we used conditionally deficient mice that harbor floxed Gfi1b alleles and one EpoR-Cre knock-in allele. We used fetal liver cells from wild type C57BL/6 embryos or conditional Gfi1b knock-out embryos at day 14.5 p.c., both carrying one EpoR-cre knock-in allele. Ter119 positive erythroid cells were isolated by flow cytometry and RNA from these cells was isolated using the Trizol procedure according to the manufacturers instructions for gene expression analysis on Affymetrix Gene 1.0 ST arrays (GPL 6246) We used microarray-based gene expression profiling to analyze the effect of loss of Gfi1b expression in Ter119 positive erythroid cells from mouse fetal liver at day 14.5 post coitum.