Nucleosome Interaction Surface of Linker Histone H1c Is Distinct from That of H10
Nucleosome Interaction Surface of Linker Histone H1c Is Distinct from That of H10
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DOI：
10.1074/jbc.m110.108639
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发表时间：
2010-07-02
影响因子：
4.8
通讯作者：
Brown, David T.
中科院分区：
文献类型：
--
作者：
George, Eric M.;Izard, Tina;Brown, David T.
真核生物核小体的完整组织结构仍然没有解决，部分原因是关于H1或连接组蛋白结合位点的信息有限。H1的中心球状结构域被认为在二分体处或附近与核小体核心相互作用，并结合至少两条DNA链。我们利用定点诱变和体内光漂白，以确定残基的体细胞H1亚型H1c的球状结构域的核小体的结合。如先前对H1（0）亚型观察到的，H1c的结合残基聚集在结构域的一个面的表面上。尽管这两种亚型的球状结构域之间存在相当大的结构保守性，但H1c的结合位点的位置与H1（0）不同。我们认为，这两个接头组蛋白亚型的球状结构域将结合到核小体不同的方向，可能有助于更高层次的染色质结构异质性或与其他DNA或染色质结合蛋白的动态相互作用的差异。
The fully organized structure of the eukaryotic nucleosome remains unsolved, in part due to limited information regarding the binding site of the H1 or linker histone. The central globular domain of H1 is believed to interact with the nucleosome core at or near the dyad and to bind at least two strands of DNA. We utilized site-directed mutagenesis and in vivo photobleaching to identify residues that contribute to the binding of the globular domain of the somatic H1 subtype H1c to the nucleosome. As was previously observed for the H1(0) subtype, the binding residues for H1c are clustered on the surface of one face of the domain. Despite considerable structural conservation between the globular domains of these two subtypes, the locations of the binding sites identified for H1c are distinct from those of H1(0). We suggest that the globular domains of these two linker histone subtypes will bind to the nucleosome with distinct orientations that may contribute to higher order chromatin structure heterogeneity or to differences in dynamic interactions with other DNA or chromatin-binding proteins.