The beta-globin dominant control region: hypersensitive site 2

EMBO J. 1990 Jul;9(7):2159-67.

Abstract

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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Cell Line
  • Cloning, Molecular
  • DNA / genetics*
  • Deoxyribonuclease I*
  • Genes*
  • Genes, Dominant*
  • Globins / genetics*
  • Humans
  • Leukemia, Experimental
  • Mice
  • Mice, Transgenic
  • Molecular Sequence Data
  • Oligonucleotide Probes
  • Plasmids
  • Restriction Mapping
  • Sequence Homology, Nucleic Acid
  • Substrate Specificity
  • Transfection

Substances

  • Oligonucleotide Probes
  • Globins
  • DNA
  • Deoxyribonuclease I