Boulikas T
Can J Biochem Cell Biol. 1985 Sep;63(9):1022-32. doi: 10.1139/o85-127.
The interaction of histone H1 with oligonucleosomes was studied in 0.15 M NaCl. Exogenous calf thymus H1 was added to a mixture of oligonucleosomes, soluble in 0.15 M NaCl, and the partially precipitated chromatin was removed by centrifugation. A strong preference of H1 for the longer nucleosomes in the mixture was observed causing their precipitation and leaving the shorter oligonucleosomes preferentially soluble. Histone H1 could even discriminate in its binding between mono- and di-nucleosomes, binding to dinucleosomes and leaving the mononucleosomes preferentially soluble. On this basis a convenient method was developed for the rapid isolation of mononucleosomes. The fidelity of H1 reconstitution to the oligonucleosomes under these conditions was suggested employing zero-length carbodiimide cross-linking and radioiodinated H1. This fraction of mononucleosomes displays significantly higher levels in the more hydrophilic H3.2 and H3.3, as well as H2A.2 and H2A.3 variant histone forms, compared with bulk chromatin. The, presumably, lower affinity of histone H1 for this subfraction of mononucleosomes is discussed.
在0.15M NaCl中研究了组蛋白H1与寡核小体的相互作用。将外源小牛胸腺H1添加到可溶于0.15M NaCl的寡核小体混合物中，通过离心去除部分沉淀的染色质。观察到H1对混合物中较长核小体有强烈偏好，导致其沉淀，而使较短的寡核小体优先保持可溶状态。组蛋白H1甚至在其与单核小体和双核小体的结合上具有区分性，它与双核小体结合，而使单核小体优先保持可溶状态。在此基础上，开发了一种快速分离单核小体的简便方法。利用零长度碳二亚胺交联和放射性碘化H1，表明在这些条件下H1重构到寡核小体上的保真度。与整体染色质相比，这部分单核小体在亲水性更强的H3.2和H3.3以及H2A.2和H2A.3变体组蛋白形式中显示出显著更高的水平。讨论了组蛋白H1对这部分单核小体的亲和力可能较低的情况。
