Distinct cohesin complexes organize meiotic chromosome domains
Distinct cohesin complexes organize meiotic chromosome domains
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DOI：
10.1126/science.1083634
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发表时间：
2003-05-16
期刊：
影响因子：
56.9
通讯作者：
Watanabe, Y
中科院分区：
文献类型：
--
作者：
Kitajima, TS;Yokobayashi, S;Watanabe, Y
着丝粒上的减数分裂内聚物与染色体臂上的减数分裂内聚物表现不同，但这些差异的基础仍然难以捉摸。在减数分裂过程中，分裂酵母黏结蛋白分子Rec8在很大程度上取代了其有丝分裂对应物Rad21/Scc1。在这里，我们发现沿染色体臂的Rec8复合体含有Rec11，而在着丝粒附近的复合体有一个不同的伙伴亚基Psc3。臂相关的Rec8-Rec11复合体对减数分裂重组至关重要。Rec8-Psc3复合物包括两种不同类型的组件。首先，Rec8-Psc3复合体依赖于组蛋白甲基化导向的异染色质进行定位，并且是减数分裂II期间内聚所必需的。其次，中心核心Rec8-Psc3复合体的形成独立于异染色质，可能是在减数分裂中建立单极附着所必需的。这些发现定义了染色体不同区域内聚蛋白复合体的不同组装模式和功能。
Meiotic cohesin complexes at centromeres behave differently from those along chromosome arms, but the basis for these differences has remained elusive. The fission yeast cohesin molecule Rec8 largely replaces its mitotic counterpart, Rad21/Scc1, along the entire chromosome during meiosis. Here we show that Rec8 complexes along chromosome arms contain Rec11, whereas those in the vicinity of centromeres have a different partner subunit, Psc3. The arm-associated Rec8-Rec11 complexes are critical for meiotic recombination. The Rec8-Psc3 complexes comprise two different types of assemblies. First, pericentromeric Rec8-Psc3 complexes depend on histone methylation-directed heterochromatin for their localization and are required for cohesion during meiosis II. Second, central core Rec8-Psc3 complexes form independently of heterochromatin and are presumably required for establishing monopolar attachment at meiosis I. These findings define distinct modes of assembly and functions for cohesin complexes at different regions along chromosomes.