High impact information on HBG1

• A chicken erythroid cell-specific enhancer is located in the intergenic region between the adult beta- and embryonic epsilon-globin genes [1].
• In this paper we show that the beta-globin enhancer stimulates transcription of both genes. epsilon-Globin is, however, inappropriately regulated since it is expressed in both embryonic and adult red blood cells [1].
• These results suggest that the chicken beta/epsilon-globin enhancer possesses either embryonic stage or epsilon-globin gene specificity when incorporated into the murine germ line [2].
• To determine whether this enhancer acts also on the epsilon-globin promoter, we constructed plasmids containing the enhancer and either the beta- or the epsilon-globin promoter fused to the bacterial chloramphenicol acetyltransferase gene [3].
• In vitro nuclear runoff transcription assays using erythroid nuclei from treated birds show that the mechanism of activation of the rho-globin gene is transcriptional whereas no transcriptional activation of the embryonic epsilon-globin gene occurs [4].

Biological context of HBG1

• The 5'-HS4 chicken beta-globin insulator functions as a positional enhancer blocker on chromatinized episomes in human cells, blocking the HS2 enhancer of the human beta-globin locus control region from activating a downstream epsilon-globin gene [5].
• Characterization of duck genome fragments containing beta and epsilon globin genes [6].
• The beta- and epsilon-globin genes are 1800 bp apart in both fragments, have second introns of 1100 and 1200 bp, respectively, and small first introns [6].

Anatomical context of HBG1

• As most active chromatin and hyperacetylated histones are associated with the low salt-insoluble residual nuclear material containing the nuclear matrix, we investigated whether hyperacetylated histones are bound to the beta(A)- and epsilon-globin DNA in this fraction [7].

Associations of HBG1 with chemical compounds

• However the constituent epsilon globin can be easily separated from beta H by electrophoresis on polyacrylamide gel in formic acid [8].

Other interactions of HBG1

• This enhancer lies between the adult beta-globin gene and the embryonic epsilon-globin gene, about equidistant from the two promoters [3].

Analytical, diagnostic and therapeutic context of HBG1

• In chromatin immunoprecipitation assays, we found that the beta(A)- and epsilon-globin coding regions are bound to hyperacetylated H3 and H4 [7].

References