ABSTRACT Cohesin is a ring-shaped, multi-subunit ATPase assembly that is fundamental to the spatiotemporal organization of chromosomes. The ring establishes a variety of chromosomal structures including sister chromatid cohesion and chromatin loops. At the core of the ring is a pair of highly conserved SMC (Structural Maintenance of Chromosomes) proteins, which are closed by the flexible kleisin subunit. In common with other essential SMC complexes including condensin and the SMC5-6 complex, cohesin encircles DNA inside its cavity, with the aid of HEAT (Huntingtin, elongation factor 3, protein phosphatase 2A and TOR) repeat auxiliary proteins. Through this topological embrace, cohesin is thought to establish a series of intra- and interchromosomal interactions by tethering more than one DNA molecule. Recent progress in biochemical reconstitution of cohesin provides molecular insights into how this ring complex topologically binds and mediates DNA-DNA interactions. Here, I review these studies and discuss how cohesin mediates such chromosome interactions.

中文翻译：

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DNA 进入、退出和粘连蛋白的第二次 DNA 捕获：生化实验的见解


摘要粘连蛋白是一种环形多亚基 ATP 酶组装体，是染色体时空组织的基础。该环建立了多种染色体结构，包括姐妹染色单体内聚力和染色质环。该环的核心是一对高度保守的 SMC（染色体结构维护）蛋白，它们被灵活的 kleisin 亚基封闭。与其他重要的 SMC 复合物（包括凝缩蛋白和 SMC5-6 复合物）一样，粘连蛋白在 HEAT（亨廷顿蛋白、延伸因子 3、蛋白磷酸酶 2A 和 TOR）重复辅助蛋白的帮助下将 DNA 包围在其腔内。通过这种拓扑拥抱，粘连蛋白被认为通过束缚多个 DNA 分子来建立一系列染色体内和染色体间相互作用。粘连蛋白生化重建的最新进展为了解这种环状复合物如何拓扑结合和介导 DNA-DNA 相互作用提供了分子见解。在这里，我回顾了这些研究并讨论了粘连蛋白如何介导这种染色体相互作用。