Hemminki K, Vauhkonen M
Biochim Biophys Acta. 1977 Jan 3;474(1):109-16. doi: 10.1016/0005-2787(77)90218-0.
Hen oviduct chromatin was digested with DNAase II and two fractions were isolated: MgCl2-insoluble chromatin and MgCl2-soluble chromatin. The former contained 14 and 50% of the total DNA after a digestion time of 3 and 30 min, respectively. The fraction was characterized in sucrose gradients by a peak sedimenting at 11S. In the course of DNAase digestion this fraction lost most of its estrogen receptors as assayed by [3H]estradiol exchange reaction. The specific radioactivity of chromatin was particularly low in the 11S region. The MgCl2-soluble chromatin contained at most 5.1% of the total DNA. In sucrose gradients the fraction displayed peaks at 4S and 14S. After a 30 min DNAase digestion the specific radioactivity of chromatin in this fraction exceeded that of the MgCl2-insoluble fraction 7.7 fold. Material sedimenting at 14 S and at larger S values was enriched in estrogen receptors. The results suggest that estrogen receptors are unevenly distributed on hen oviduct chromain.
用脱氧核糖核酸酶II消化母鸡输卵管染色质，并分离出两个组分：氯化镁不溶性染色质和氯化镁可溶性染色质。在分别消化3分钟和30分钟后，前者分别含有总DNA的14%和50%。该组分在蔗糖梯度中表现为一个在11S处沉降的峰。在脱氧核糖核酸酶消化过程中，通过[3H]雌二醇交换反应测定，该组分失去了大部分雌激素受体。染色质的比放射性在11S区域特别低。氯化镁可溶性染色质最多含有总DNA的5.1%。在蔗糖梯度中，该组分在4S和14S处出现峰。经过30分钟的脱氧核糖核酸酶消化后，该组分中染色质的比放射性超过氯化镁不溶性组分7.7倍。在14S及更大S值处沉降的物质富含雌激素受体。结果表明，雌激素受体在母鸡输卵管染色质上分布不均。
