The human SWI/SNF-B chromatin-remodeling complex is related to yeast Rsc and localizes at kinetochores of mitotic chromosomes
The human SWI/SNF-B chromatin-remodeling complex is related to yeast Rsc and localizes at kinetochores of mitotic chromosomes
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DOI：
10.1073/pnas.240208597
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发表时间：
2000-11-21
影响因子：
11.1
通讯作者：
Wang, WD
中科院分区：
文献类型：
--
作者：
Xue, YT;Canman, JC;Wang, WD
SWI/SNF 染色质重塑复合物家族通过帮助转录因子接近染色质中的靶标来促进基因表达。 SWI/SNF 和 Rsc 是该酵母家族的独特成员。它们具有相似的蛋白质成分和催化活性，但生物学功能不同。 Rsc 是通过有丝分裂进行细胞周期进程所必需的，而 SWI/SNF 则不然。该家族的人类复合物也已被鉴定，通常被认为与酵母 SWI/SNF 相关。然而，迄今为止识别的所有人类亚基与 SWI/SNF 和 Rsc 的组成部分同样相似，因此存在部分或全部人类复合物与 Rsc 相当相关的可能性。在这里，我们提供证据表明先前识别的人类 SWI/SNF-B 复合物确实属于 Rsc 类型。它包含 Rsc 和 SWI/SNF 中保守的六个成分。重要的是，它有一个独特的亚基 BAF180，它具有 Rsc 三个组件特有的一组独特的结构基序。在已知与酵母复合物中的那些相关的两种哺乳动物 ATP 酶中，人类 SWI/SNF-B 只包含在细胞生长过程中发挥与 Rsc 类似功能的同源物。使用 BAF180 抗体进行的免疫荧光研究表明，SWI/SNF-B 在有丝分裂过程中定位于染色体的着丝粒。我们的数据表明，SWI/SNF-B 和 Rsc 代表从酵母到人类保守的染色质重塑复合物的新亚家族，并且可能参与有丝分裂染色体着丝粒的细胞分裂。
The SWI/SNF family of chromatin-remodeling complexes facilitates gene expression by helping transcription factors gain access to their targets in chromatin. SWI/SNF and Rsc are distinctive members of this family from yeast. They have similar protein components and catalytic activities but differ in biological function. Rsc is required for cell cycle progression through mitosis, whereas SWI/ SNF is not, Human complexes of this family have also been identified, which have often been considered related to yeast SWI/SNF. However, all human subunits identified to date are equally similar to components of both SWI/SNF and Rsc, leaving open the possibility that some or all of the human complexes are rather related to Rsc, Here, we present evidence that the previously identified human SWI/SNF-B complex is indeed of the Rsc type. It contains six components conserved in both Rsc and SWI/SNF. Importantly, it has a unique subunit, BAF180, that harbors a distinctive set of structural motifs characteristic of three components of Rsc, Of the two mammalian ATPases known to be related to those in the yeast complexes, human SWI/SNF-B contains only the homolog that functions like Rsc during cell growth. Immunofluorescence studies with a BAF180 antibody revealed that SWI/ SNF-B localizes at the kinetochores of chromosomes during mitosis, Our data suggest that SWI/SNF-B and Rsc represent a novel subfamily of chromatin-remodeling complexes conserved from yeast to human, and could participate in cell division at kinetochores of mitotic chromosomes.