Suppr超能文献

组蛋白表面可及性决定了依赖于 RSC 的核小体迁移的方向。

Histone protein surface accessibility dictates direction of RSC-dependent nucleosome mobilization.

机构信息

Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, NY 14642, USA.

出版信息

Nucleic Acids Res. 2022 Oct 14;50(18):10376-10384. doi: 10.1093/nar/gkac790.

Abstract

Chromatin remodeling enzymes use energy derived from ATP hydrolysis to mobilize nucleosomes and alter their structure to facilitate DNA access. The Remodels the Structure of Chromatin (RSC) complex has been extensively studied, yet aspects of how this complex functionally interacts with nucleosomes remain unclear. We introduce a steric mapping approach to determine how RSC activity depends on interaction with specific surfaces within the nucleosome. We find that blocking SHL + 4.5/-4.5 via streptavidin binding to the H2A N-terminal tail domains results in inhibition of RSC nucleosome mobilization. However, restriction enzyme assays indicate that remodeling-dependent exposure of an internal DNA site near the nucleosome dyad is not affected. In contrast, occlusion of both protein faces of the nucleosome by streptavidin attachment near the acidic patch completely blocks both remodeling-dependent nucleosome mobilization and internal DNA site exposure. However, we observed partial inhibition when only one protein surface is occluded, consistent with abrogation of one of two productive RSC binding orientations. Our results indicate that nucleosome mobilization requires RSC access to the trailing but not the leading protein surface, and reveals a mechanism by which RSC and related complexes may drive unidirectional movement of nucleosomes to regulate cis-acting DNA sequences in vivo.

摘要

染色质重塑酶利用 ATP 水解产生的能量来移动核小体并改变其结构,以促进 DNA 的进入。Remodels the Structure of Chromatin (RSC) 复合物已经得到了广泛的研究,但该复合物如何与核小体进行功能相互作用的某些方面仍不清楚。我们引入了一种空间映射方法来确定 RSC 活性如何依赖于与核小体内部特定表面的相互作用。我们发现,通过将链霉亲和素结合到 H2A N 端尾部结构域来阻断 SHL+4.5/-4.5,会导致 RSC 核小体移动的抑制。然而,限制性内切酶测定表明,重塑依赖性暴露核小体二分体附近的内部 DNA 位点不受影响。相比之下,通过在酸性斑块附近将链霉亲和素附着在核小体的两个蛋白质表面上进行闭塞,完全阻止了重塑依赖性核小体移动和内部 DNA 位点暴露。然而,当只有一个蛋白质表面被闭塞时,我们观察到部分抑制,这与两种有生产力的 RSC 结合取向之一的废除一致。我们的结果表明,核小体的移动需要 RSC 能够进入尾随的但不是领头的蛋白质表面,这揭示了一种机制,通过该机制,RSC 和相关复合物可以驱动核小体的单向运动,以在体内调节顺式作用 DNA 序列。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/dba3/9561379/08b03e86fa64/gkac790fig1.jpg

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验