Chicken erythrocyte beta-globin chromatin: enhanced solubility is a direct consequence of induced histone hyperacetylation.
Chicken immature red blood cells were incubated for 1 hour in Swim's medium containing 3H-acetate and 10 mM n-butyrate. During the incubation period, the small percentage of dynamically acetylated and deacetylated histone is radiolabeled and hyperacetylated. A second effect of the n-butyrate incubation is to shift a small subset of nucleohistone into a soluble form. This chromatin is predominantly polynucleosome size (approximately dimer to pentamer) and can be separated from soluble mononucleosomes by 5-30% sucrose gradient centrifugation. The soluble polynucleosomes are 25-30 fold enriched for adult beta-globin (beta A) DNA and contain the hyperacetylated histones. We have tested whether histone hyperacetylation is responsible for the enhanced beta-globin chromatin solubility by in vitro deacetylation of the soluble chromatin histones. This procedure converts the beta-globin polynucleosomes to an insoluble form, demonstrating that histone hyperacetylation is in fact directly responsible for the increased solubility of the beta A chromatin.
Alonso
W R
WR
Department of Biochemical and Biophysical Sciences, University of Houston, TX 77004.
Ferris
R C
RC
Zhang
D E
DE
Nelson
D A
DA
D000107:Acetylation; D000818:Animals; D002645:Chickens; D002843:Chromatin / Q000378:metabolism / Q000648:ultrastructure*; D004247:DNA / Q000097:blood / Q000235:genetics / Q000302:isolation & purification; D004912:Erythrocytes / Q000378:metabolism*; D005796:Genes; D005914:Globins / Q000235:genetics*; D006441:Hemoglobin A / Q000235:genetics; D006657:Histones / Q000378:metabolism*
D002843:Chromatin; D006657:Histones; D005914:Globins; D004247:DNA; D006441:Hemoglobin A