首页> 美国卫生研究院文献>Genes Development >The Prp8 RNase H-like domain inhibits Brr2-mediated U4/U6 snRNA unwinding by blocking Brr2 loading onto the U4 snRNA
【2h】

The Prp8 RNase H-like domain inhibits Brr2-mediated U4/U6 snRNA unwinding by blocking Brr2 loading onto the U4 snRNA

机译:Prp8 RNase H样结构域通过阻止Brr2加载到U4 snRNA上来抑制Brr2介导的U4 / U6 snRNA释放。

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务,本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文,但由于OA文献来源多样且变更频繁,仍可能出现获取不到、文献不完整或与标题不符等情况,如果获取不到我们将提供退款服务。请知悉。

摘要

The spliceosomal RNA helicase Brr2 catalyzes unwinding of the U4/U6 snRNA duplex, an essential step for spliceosome catalytic activation. Brr2 is regulated in part by the spliceosomal Prp8 protein by an unknown mechanism. We demonstrate that the RNase H (RH) domain of yeast Prp8 binds U4/U6 small nuclear RNA (snRNA) with the single-stranded regions of U4 and U6 preceding U4/U6 stem I, contributing to its binding. Via cross-linking coupled with mass spectrometry, we identify RH domain residues that contact the U4/U6 snRNA. We further demonstrate that the same single-stranded region of U4 preceding U4/U6 stem I is recognized by Brr2, indicating that it translocates along U4 and first unwinds stem I of the U4/U6 duplex. Finally, we show that the RH domain of Prp8 interferes with U4/U6 unwinding by blocking Brr2's interaction with the U4 snRNA. Our data reveal a novel mechanism whereby Prp8 negatively regulates Brr2 and potentially prevents premature U4/U6 unwinding during splicing. They also support the idea that the RH domain acts as a platform for the exchange of U6 snRNA for U1 at the 5′ splice site. Our results provide insights into the mechanism whereby Brr2 unwinds U4/U6 and show how this activity is potentially regulated prior to spliceosome activation.
机译:剪接体RNA解旋酶Brr2催化展开U4 / U6 snRNA双链体,这是剪接体催化激活的重要步骤。 Brr2部分受剪接体Prp8蛋白的调控,其机制未知。我们证明酵母Prp8的RNase H(RH)域结合U4 / U6茎I之前的U4和U6单链区与U4 / U6小核RNA(snRNA)结合,有助于其结合。通过与质谱联用的交联,我们确定接触U4 / U6 snRNA的RH域残基。我们进一步证明,Brr2识别U4 / U6茎I之前的U4相同的单链区域,表明它沿着U4移位并首先展开U4 / U6双链体的茎I。最后,我们显示Prp8的RH结构域通过阻断Brr2与U4 snRNA的相互作用而干扰U4 / U6的解链。我们的数据揭示了一种新颖的机制,其中Prp8负调控Brr2并潜在地防止了剪接过程中过早的U4 / U6退绕。他们还支持RH结构域充当5'剪接位点处U6 snRNA与U1交换平台的想法。我们的结果提供了对Brr2解开U4 / U6的机制的见解,并显示了在剪接体激活之前如何潜在地调节这种活性。

著录项

相似文献

  • 外文文献
代理获取

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