...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Selective abolition of pancreatic RNase binding to its inhibitor protein
【24h】

Selective abolition of pancreatic RNase binding to its inhibitor protein

机译：选择性取消胰腺RNase与其抑制剂蛋白的结合

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

We have modified Rnase inhibitor (RI) protein so that it no longer detectably binds pancreatic Rnases but retains near-native affinity for human angiogenin (ANG). The K_I value for Rnase A is increased by a factor of > 10~8, from 36 Fm to >4 Μm, and the selectivity factor for ANG is now >10~9. This dramatic change was achieved by remodeling the human RI loop segment Cys-408-Leu-409-Gly-410, which makes minor interactions with pancreatic Rnase but does not contact ANG. The modifications selected were designed to sterically hinder docking of the undesired ligand. Three of the variants tested (C408W, G410W, and C408W/G410W) bind Rnase A with almost the same avidity as WT RI. However, combination of the 408/410 double Trp replacement with deletion of the intervening residue, Leu-409, was sufficient to abolish inhibition of Rnase A and human pancreatic Rnase. The K_I value for ANG with the deletion variant is 1.1 Fm, only 2-fold higher than with WT RI. This variant may have potential utility both as an anticancer drug targeting ANG and as a tool for the investigation of the biological function of ANG. More generally, these findings demonstrate that a protein-protein interaction can be effectively and specifically disrupted by redesigning an interface region that makes no major energetic contribution to complex stability. This finding, in turn, may have implications for the development of small molecules that modulate protein-protein interactions.
机译：我们已经修饰了Rnase抑制剂（RI）蛋白，使其不再可检测地结合胰腺Rnases，但保留了与人血管生成素（ANG）接近的天然亲和力。 Rnase A的K_I值从36 Fm增加到> 4μm，增加了10〜8倍，而ANG的选择性因子现在> 10〜9。通过重塑人RI环片段Cys-408-Leu-409-Gly-410实现了这一巨大变化，该片段与胰腺Rnase的相互作用很小，但不与ANG接触。选择的修饰被设计为在空间上阻碍不希望的配体的对接。测试的三个变体（C408W，G410W和C408W / G410W）以与WT RI几乎相同的亲和力结合RnaseA。但是，将408/410双重Trp替换与中间残基Leu-409缺失相结合就足以消除对Rnase A和人胰腺Rnase的抑制作用。具有缺失变体的ANG的K_I值为1.1 Fm，仅比WT RI高2倍。该变体既可以作为靶向ANG的抗癌药物又可以作为研究ANG的生物学功能的工具具有潜在的实用性。更普遍地，这些发现表明，通过重新设计对复杂稳定性没有主要能量贡献的界面区域，可以有效地且特异性地破坏蛋白质间相互作用。反过来，这一发现可能对调节蛋白质-蛋白质相互作用的小分子的发展有影响。

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