• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Molecular Biology >The structure and conformation of Lys63-linked tetraubiquitin.
【24h】

The structure and conformation of Lys63-linked tetraubiquitin.

机译：Lys63连接的四泛素的结构和构象。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Ubiquitination involves the covalent attachment of the ubiquitin (Ub) C-terminus to the lysine side chain of a substrate protein by an isopeptide bond. The modification can comprise a single Ub moiety or a chain of Ub molecules joined by isopeptide bonds between the C-terminus of one Ub with one of the seven lysine residues in the next Ub. Modification of substrate proteins with Lys63-linked poly-Ub plays a key nondegradative signaling role in many biological processes, including DNA repair and nuclear factor-kappaB activation, whereas substrates modified by Lys48-linked chains are targeted to the proteasome for degradation. The distinct signaling properties of alternatively linked Ub chains presumably stem from structural differences that can be distinguished by effector proteins. We have determined the crystal structure of Lys63 tetra-Ub at a resolution of 1.96 A and performed small-angle X-ray scattering experiments and molecular dynamics simulations to probe the conformation of Lys63 tetra-Ub in solution. The chain adopts a highly extended conformation in the crystal, in contrast with the compact globular fold of Lys48 tetra-Ub. Small-angle X-ray scattering experiments show that the Lys63 tetra-Ub chain is dynamic in solution, adopting an ensemble of conformations that are more compact than the extended form in the crystal. The results of these studies provide a basis for understanding the differences in the behavior and recognition of Lys63 poly-Ub chains.
机译：泛素化涉及通过异肽键将泛素（Ub）C端共价附于底物蛋白的赖氨酸侧链。该修饰可以包含单个Ub部分或Ub分子链，该Ub分子链通过一个Ub的C末端与下一Ub中的七个赖氨酸残基之一之间的异肽键连接。用Lys63连接的多Ub修饰底物蛋白在许多生物学过程中起着关键的非降解信号转导作用，包括DNA修复和核因子kappaB激活，而通过Lys48连接的链修饰的底物则靶向蛋白酶体进行降解。交替连接的Ub链的独特信号传导特性大概是由可以通过效应子蛋白区分的结构差异引起的。我们以1.96 A的分辨率确定了Lys63 tetra-Ub的晶体结构，并进行了小角度X射线散射实验和分子动力学模拟，以探索溶液中Lys63 tetra-Ub的构象。与Lys48 tetra-Ub的紧密球状褶皱相比，该链在晶体中采用高度延伸的构象。小角X射线散射实验表明，Lys63四Ub链在溶液中是动态的，采用了比晶体中的扩展形式更紧密的构象集合。这些研究结果为理解Lys63 poly-Ub链的行为差异和识别提供了基础。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号