ABSTRACT
DNase II shearing and MgCl2 precipitation of chick oviduct chromatin were applied to prepare fractions which resembled template-active and template-inactive chromatin fraction as described for other tissues. The labelling of these preparations with [3H]oestradiol was studied in short-term tissue cultures. The MgCl2 soluble (∼ template-active) chromatin bound 1.8 times more oestradiol than the MgCl2 insoluble chromatin when immature chicks were used. The proportion was 4.3-fold in oestrogen stimulated chicks and 4.6-fold in laying hens. Similar results were obtained with an oestrogen exchange assay which measured the concentration of endogenous receptors. These data suggest that hormone stimulation is accompanied by a selective activation of oviduct chromatin leading to an enrichment of acceptor sites for oestradiol receptors in the template-active chromatin fraction.
Release of a globin gene enriched chromatin fraction from chicken erythrocyte nuclei following DNase II digestion