A tDNA establishes cohesion of a neighboring silent chromatin domain
A tDNA establishes cohesion of a neighboring silent chromatin domain
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DOI：
10.1101/gad.1583807
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发表时间：
2007-09-01
影响因子：
10.5
通讯作者：
Gartenberg, Marc R.
中科院分区：
文献类型：
--
作者：
Dubey, Rudra N.;Gartenberg, Marc R.
DNA 复制产生姐妹染色单体对，这些姐妹染色单体对相互结合直至后期开始。这个过程被称为姐妹染色单体凝聚，需要位于着丝粒和基因汇聚位点的多亚基黏连蛋白复合物。在芽殖酵母的 HMR 交配型位点，粘连蛋白与称为沉默染色质的异染色质样结构结合。在本报告中，我们表明沉默染色质对于复制位点的凝聚力是必要的，但还不够。还需要界定沉默染色质结构域的 tRNA 基因 (tDNA)，以及结合该基因的 TFIIIB 和 RSC 复合物的亚基。非 tDNA 边界元件不能取代 tDNA 的内聚力，这表明屏障活动不是造成这种现象的原因。结果揭示了 tDNA 和 RNA 聚合酶 III 相关蛋白在姐妹染色单体凝聚力建立中的所有意想不到的作用。
DNA replication generates sister chromatid pairs that are bound to one another until anaphase onset. The process, termed sister chromatid cohesion, requires the multisubunit cohesin complex that resides at centromeres and sites where genes converge. At the HMR mating-type locus of budding yeast, cohesin associates with a heterochromatin-like structure known as silent chromatin. In this report, we show that silent chromatin is necessary but not sufficient for cohesion of the replicating locus. A tRNA gene (tDNA) that delimits the silent chromatin domain is also required, as are subunits of the TFIIIB and RSC complexes that bind the gene. Non-tDNA boundary elements do not substitute for tDNAs in cohesion, suggesting that barrier activity is not responsible for the phenomenon. The results reveal ail unexpected role for tDNAs and RNA polymerase Ill-associated proteins in establishment of sister chromatid cohesion.