...
首页> 外文期刊>Molecular and Cellular Biology >A Gain-of-Function Mutation in the Second Tetratricopeptide Repeat of TFIIIC131 Relieves Autoinhibition of Brf1 Binding.
【24h】

A Gain-of-Function Mutation in the Second Tetratricopeptide Repeat of TFIIIC131 Relieves Autoinhibition of Brf1 Binding.

机译:

获取原文
获取原文并翻译 | 示例
           

摘要

The interaction between the tetratricopeptide repeat (TPR)-containing subunit of TFIIIC, TFIIIC131, and the TFIIB-related factor Brf1 represents a limiting step in the assembly of the RNA polymerase III (pol III) initiation factor TFIIIB. This assembly reaction is facilitated by dominant mutations that map in and around TPR2. Structural modeling of TPR1 to TPR3 from TFIIIC131 shows that one such mutation, PCF1-2, alters a residue in the ligand-binding groove of the TPR superhelix whereas another mutation, PCF1-1, changes a surface-accessible residue on the back side of the TPR superhelix. In this work, we show that the PCF1-1 mutation (H190Y) increases the binding affinity for Brf1, but does not affect the binding affinity for Bdp1, in the TFIIIC-dependent assembly of TFIIIB. Interestingly, binding studies with TFIIIC131 fragments indicate that Brf1 does not interact directly at the site of the PCF1-1 mutation. Rather, the data suggest that the mutation overcomes the previously documented autoinhibition of Brf1 binding. These findings together with the results from site-directed mutagenesis support the hypothesis that gain-of-function mutations at amino acid 190 in TPR2 stabilize an alternative conformation of TFIIIC131 that promotes its interaction with Brf1.

著录项

相似文献

  • 外文文献
  • 中文文献
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