• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Molecular Biology >RNA tertiary interactions mediate native collapse of a bacterial group I ribozyme.
【24h】

RNA tertiary interactions mediate native collapse of a bacterial group I ribozyme.

机译：RNA第三级相互作用介导细菌I类核酶的天然崩溃。

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

Large RNAs collapse into compact intermediates in the presence of counterions before folding to the native state. We previously found that collapse of a bacterial group I ribozyme correlates with the formation of helices within the ribozyme core, but occurs at Mg2+ concentrations too low to support stable tertiary structure and catalytic activity. Here, using small-angle X-ray scattering, we show that Mg2+-induced collapse is a cooperative folding transition that can be fit by a two-state model. The Mg2+ dependence of collapse is similar to the Mg2+ dependence of helix assembly measured by partial ribonuclease T1 digestion and of an unfolding transition measured by UV hypochromicity. The correspondence between multiple probes of RNA structure further supports a two-state model. A mutation that disrupts tertiary contacts between the L9 tetraloop and its helical receptor destabilized the compact state by 0.8 kcal/mol, while mutations in the central triplex were less destabilizing. These results show thatnative tertiary interactions stabilize the compact folding intermediates under conditions in which the RNA backbone remains accessible to solvent.
机译：大RNA在抗衡离子存在下折叠成紧密的中间体，然后折叠成天然状态。我们先前发现细菌I类核酶的崩溃与核酶核心内螺旋的形成有关，但发生在Mg2 +浓度太低而无法支持稳定的三级结构和催化活性的情况下。在这里，使用小角度X射线散射，我们显示Mg2 +引起的塌陷是一种可通过二态模型拟合的协同折叠过渡。崩溃的Mg2 +依赖性类似于通过部分核糖核酸酶T1消化测量的螺旋装配的Mg2 +依赖性，以及通过UV变色测量的展开转变的Mg2 +依赖性。 RNA结构的多个探针之间的对应关系进一步支持两态模型。破坏L9四环与其螺旋受体之间三级接触的突变使紧密状态的稳定度降低了0.8 kcal / mol，而中央三链体的突变破坏了稳定性。这些结果表明，在RNA主链保持可接触溶剂的条件下，天然三级相互作用稳定了紧密折叠的中间体。

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