Integrative Modeling of a Sin3/HDAC Complex Sub-structure
Integrative Modeling of a Sin3/HDAC Complex Sub-structure
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DOI：
10.1016/j.celrep.2020.03.080
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发表时间：
2020-04-14
期刊：
影响因子：
8.8
通讯作者：
Washburn, Michael P.
中科院分区：
文献类型：
--
作者：
Banks, Charles A. S.;Zhang, Ying;Washburn, Michael P.
Sin3/HDAC复合物通过去乙酰化组蛋白、凝聚染色质和调节基因表达发挥作用。虽然用于构建这些复合物的成分已经被很好地定义，但我们对围绕脚手架蛋白SIN3A组装的Sin3/HDAC亚基的结构仍然知之甚少。为了表征Sin3亚基的空间排列，我们结合了Halo亲和捕获、化学交联和高分辨率质谱（XL-MS）来确定亚基间的距离约束，鉴定了13个Sin3亚基的66个蛋白间和63个自交联。通过将自交联映射到现有结构上来评估交联的真实性，我们使用了蛋白间交联的距离限制来指导Sin3复杂亚结构的组装。我们确定了SAP30L、HDAC1、SUDS3、HDAC2和ING1亚基在SIN3A支架周围的相对位置。该亚基的结构表明，多种因素有空间聚集在一起，共同影响催化亚基HDAC1的行为。
Sin3/HDAC complexes function by deacetylating histones, condensing chromatin, and modulating gene expression. Although components used to build these complexes have been well defined, we still have only a limited understanding of the structure of the Sin3/HDAC subunits assembled around the scaffolding protein SIN3A. To characterize the spatial arrangement of Sin3 subunits, we combined Halo affinity capture, chemical crosslinking, and high-resolution mass spectrometry (XL-MS) to determine intersubunit distance constraints, identifying 66 interprotein and 63 self-crosslinks for 13 Sin3 subunits. Having assessed crosslink authenticity by mapping self-crosslinks onto existing structures, we used distance restraints from interprotein crosslinks to guide assembly of a Sin3 complex substructure. We identified the relative positions of subunits SAP30L, HDAC1, SUDS3, HDAC2, and ING1 around the SIN3A scaffold. The architecture of this subassembly suggests that multiple factors have space to assemble to collectively influence the behavior of the catalytic subunit HDAC1.