Circular dichroism, thermal denaturation, and deoxyribonuclease I digestion studies of nucleosomes highly enriched in high mobility group proteins HMG 1 and HMG 2.
Circular dichroism, thermal denaturation, and deoxyribonuclease I digestion studies of nucleosomes highly enriched in high mobility group proteins HMG 1 and HMG 2.
复制标题
高富集高迁移率基团蛋白 HMG 1 和 HMG 2 的核小体的圆二色性、热变性和脱氧核糖核酸酶 I 消化研究。
DOI：
10.1021/bi00507a060
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发表时间：
1981
期刊：
影响因子：
2.9
通讯作者：
Rill,RL
中科院分区：
文献类型：
--
作者：
Jackson,JB;Rill,RL
摘要：从小鼠骨髓瘤细胞核中分离到盐溶(S)核小体，含有接近等摩尔的高迁移率组非组蛋白HMG-1和HMG-2，缺乏组蛋白HI。将S核小体的沉淀、近紫外圆二色谱、热变性和DNaseI酶切图谱与核小体核心或含有HI的“典型”核小体的这些性质进行比较，没有发现显著差异。这些结果表明，HMG-1和HMG-2不影响讨论-最近描述了在微球菌核酸酶非常轻微的处理后，在近生理离子条件下从小鼠骨髓瘤细胞核中分离出的一组不寻常的核小体(Jackson等，1979)。这些核小体含有明显正常的核心组蛋白(H_2A、H_2B、H_3、H_4)和约200bp1长度的DNA，但缺乏组蛋白HI，而是含有两种接近化学计量的高迁移率基团非组蛋白染色体蛋白：HMG-1和HMG-2。它们还富含少量的其他非组蛋白。
James B. Jackson* and Randolph L. Rill* abstract: Salt-soluble (S) nucleosomes that contain near equimolar high mobility group nonhistone chromosomal proteins HMG 1 and HMG 2 and lack histone HI were isolated from mouse myeloma nuclei. Comparisons of the sedimen-tation, near-UV circular dichroism, thermal denaturation, and pattern of DNase I digestion of S nucleosomes with these properties of nucleosome cores or “typical” nucleosomes containing HI did not detect significant differences. These results indicate that HMG 1 and 2 do notaffect the confer-va have recently described the isolation of an unusual subset of nucleosomes that are released from mouse myeloma nuclei under near-physiological ionic conditions after very slight treatment with micrococcal nuclease (Jackson et al., 1979). These nucleosomes contain an apparently normal complement of core histones (H2a, H2b, H3, H4) and ca. 200 bp1 length DNA, but lack histone HI, and instead contain near-stoichiometric amounts of two high mobility group nonhistone chromosomal proteins, HMG 1 and HMG 2. They are also enrichedin lesser amounts of several other nonhistone proteins.