Williamson P, Felsenfeld G
Biochemistry. 1978 Dec 26;17(26):5695-705. doi: 10.1021/bi00619a015.
Purified core histones (H2A, H2B, H3, and H4) and bacteriophage T7 DNA have been reconstituted to form a nucleoprotein complex, and the properties of this complex as a template for transcription by Escherichia coli RNA polymerase have been studied. At low ionic strength, RNA chain elongation rates are slow, and the chains produced even after long incubation are short. At higher salt concentrations, chain-elongation rates approach those on naked DNA. Since the salt concentrations used are not in themselves sufficient to dissociate the histones from the DNA, some mechanism must exist that permits passage of the polymerase through histone-covered regions.
已将纯化的核心组蛋白（H2A、H2B、H3和H4）与噬菌体T7 DNA重组形成核蛋白复合物，并研究了该复合物作为大肠杆菌RNA聚合酶转录模板的特性。在低离子强度下，RNA链延伸速率缓慢，即使长时间孵育后产生的链也很短。在较高盐浓度下，链延伸速率接近裸DNA上的速率。由于所用盐浓度本身不足以使组蛋白与DNA解离，必然存在某种机制允许聚合酶通过组蛋白覆盖区域。
