Dimethyl sulfoxide (DMSO) induction of mouse erythroleukemia (MEL) cells represents a well-defined in vitro system of terminal erythroid differentiation. We have studied the molecular mechanisms of transcriptional activation of the mouse βmaj globin gene during MEL cell differentiation by analyzing nuclear factor-DNA interactions in vivo at the gene's upstream promoter and a distal enhancer, 5′HS-2. Genomic footprinting data indicate that three motifs, CAC, NF-E2/AP1, and GATA-1, of the 5′HS-2 enhancer are bound with nuclear factors in MEL cells both prior to and after DMSO induction. No obvious conformational change of these nuclear factor-DNA complexes could be detected upon terminal differentiation of MEL cells. On the other hand, DMSO induction of MEL cells leads to the formation of specific nuclear factor-DNA complexes at several transcriptional regulatory elements of the mouse βmaj globin upstream promoter. Our genomic footprinting data have interesting implications with respect to the molecular mechanisms of transcriptional regulation and chromatin change of the mouse βmaj globin gene during erythroid differentiation.
ASJC Scopus subject areas