The β-globin dominant control region: hypersensitive site 2.
The Dominant Control Region (DCR) of the human beta-globin gene locus consists of four strong hypersensitive sites (HSS) upstream of the epsilon-globin gene. Addition of these sites confers copy number dependent expression on the human beta-globin gene in murine erythroleukaemia cells and transgenic mice, at levels comparable with the endogenous mouse globin genes. We have shown previously that a 1.9 kb fragment comprising HSS 2 accounts for 40-50% of the full effect of the DCR. In this paper we describe a deletional analysis of HSS 2. We show that a 225 bp fragment is sufficient to direct high levels of expression of the human beta-globin gene which is copy number dependent and integration site independent. This 225 bp fragment overlaps the major region that is hypersensitive 'in vivo'. DNase I footprinting shows the presence of four binding sites for the erythroid specific protein NF-E1; the three other footprinted regions display a remarkable redundancy of the sequence GGTGG and bind a number of proteins including Sp1 and the CACC box protein. The significance of these results for the regulation of globin gene expression is discussed.
|Keywords||*Deoxyribonuclease I, *Genes, Dominant, *Genes, Structural, 0 (Oligonucleotide Probes), 0 (Plasmids), 9004-22-2 (Globins), 9007-49-2 (dna), Animals, Base Sequence, Cell Line, Cloning, Molecular, Comparative Study, DNA/*genetics, EC 22.214.171.124 (Deoxyribonuclease I), Globins/*genetics, Human, Leukemia, Experimental, Mice, Mice, Transgenic, Molecular Sequence Data, Oligonucleotide Probes, Plasmids, Restriction Mapping, Sequence Homology, Nucleic Acid, Substrate Specificity, Support, Non-U.S. Gov't, Support, U.S. Gov't, P.H.S., Transfection|
Philipsen, J.N.J., Talbot, D., Fraser, P., & Grosveld, F.G.. (1990). The β-globin dominant control region: hypersensitive site 2.. EMBO Journal, 9, 2159–2167. Retrieved from http://hdl.handle.net/1765/2452