Oda T, Omura S, Hidaka H
Acta Med Okayama. 1977 Oct;31(5):275-87.
Reconstituted complexes of DNA with histone were prepared by salt-and-urea step gradient dialysis. The DNA was complexed with histone H1, with the combination of the other four histones H2A, H2B, H3 and H4, and with whole histones. These DNA-histone complexes were purified by Bio-Gel column chromatography, and the weight ratio of histone-to-DNA was determined in each complex. The thermal denaturation profile and nuclease digestion pattern of DNA-histone H2A, H2B, H3 and H4 complex were compatible with those of the polynucleosome structure of chromatin. The template activities for transcription were compared in these DNA-histone complexes by separately measuring initiation reaction and chain elongation. The binding of histone H1 to DNA strongly inhibited the initiation, while the binding of the combination of the other four histones to DNA partially inhibited the initiation and chain elongation. The binding characteristics are discussed with regard to the role of histone H1 and the other four histones in chromatin structure and template activity.
通过盐和尿素分步梯度透析制备了DNA与组蛋白的重组复合物。DNA分别与组蛋白H1、与其他四种组蛋白H2A、H2B、H3和H4的组合以及与全组蛋白进行复合。这些DNA-组蛋白复合物通过生物凝胶柱色谱法进行纯化，并测定了每种复合物中组蛋白与DNA的重量比。DNA-组蛋白H2A、H2B、H3和H4复合物的热变性图谱和核酸酶消化模式与染色质多核小体结构的图谱相符。通过分别测量起始反应和链延伸，比较了这些DNA-组蛋白复合物的转录模板活性。组蛋白H1与DNA的结合强烈抑制起始反应，而其他四种组蛋白的组合与DNA的结合则部分抑制起始反应和链延伸。结合组蛋白H1和其他四种组蛋白在染色质结构和模板活性中的作用，对结合特性进行了讨论。
