A RSC/Nucleosome Complex Determines Chromatin Architecture and Facilitates Activator Binding
A RSC/Nucleosome Complex Determines Chromatin Architecture and Facilitates Activator Binding
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DOI：
10.1016/j.cell.2010.03.048
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发表时间：
2010-04-30
期刊：
影响因子：
64.5
通讯作者：
Ptashne, Mark
中科院分区：
文献类型：
--
作者：
Floer, Monique;Wang, Xin;Ptashne, Mark
染色质结构是如何建立的，它在转录中起什么作用？我们发现酵母调控位点UASg除了具有激活子Gal4的结合位点外，还具有RSC复合物结合的位点。RSC将核小体（明显部分解绕）定位在有利于Gal4与其位点结合的结构中。该复合体包括一个屏障，施加染色质结构的特征。在没有RSC的情况下，普通核小体侵入UASg并与Gal4竞争结合。结合我们之前的工作，结果表明，在诱导之前和诱导之后，特异性dna结合蛋白是GAL1/10基因染色质结构的主要决定因素。RSC/核小体复合物也被发现散布在酵母基因组周围。高等真核生物的RSC缺乏酵母RSC中发现的特异性dna结合决定因素，显然Gal4在这些生物中起作用，尽管存在广泛定位的核小体障碍。
How is chromatin architecture established and what role does it play in transcription? We show that the yeast regulatory locus UASg bears, in addition to binding sites for the activator Gal4, sites bound by the RSC complex. RSC positions a nucleosome, evidently partially unwound, in a structure that facilitates Gal4 binding to its sites. The complex comprises a barrier that imposes characteristic features of chromatin architecture. In the absence of RSC, ordinary nucleosomes encroach over the UASg and compete with Gal4 for binding. Taken with our previous work, the results show that both prior to and following induction, specific DNA-binding proteins are the predominant determinants of chromatin architecture at the GAL1/10 genes. RSC/nucleosome complexes are also found scattered around the yeast genome. Higher eukaryotic RSC lacks the specific DNA-binding determinants found on yeast RSC, and evidently Gal4 works in those organisms despite whatever obstacle broadly positioned nucleosomes present.