STRUCTURAL BASIS OF RNA THERMOSTABILITY

RNA 热稳定性的结构基础

• 批准号: 8168622
• 负责人: Tobin R Sosnick
• 金额: $ 0.54万
• 依托单位: ILLINOIS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8168622
• 关键词: Adopted; Agreement; Bacillus stearothermophilus; Bacillus subtilis; Computer Retrieval of Information on Scientific Projects Database; Data; Funding; Grant; Holoenzymes; Homologous Gene; Institution; Measurement; Modeling; Molecular; Molecular Models; Monovalent Cations; RNA; RNase P; Relative (related person); Research; Research Personnel; Resources; Ribonucleoproteins; Roentgen Rays; Side; Source; Specificity; Structure; United States National Institutes of Health; base; molecular modeling; particle; thermostability

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. All bacterial RNase P RNAs are composed of two independently folding domains. These domains pack against each other in the crystal structure of the Bacillus stearothermophilus RNase P RNA. This side-by-side packing is widely assumed to be the only native structure bacterial P RNAs can adapt. Here we show using small-angle X-ray scattering, in-line probing and molecular modeling that the P RNA from Bacillus subtilis, a close homolog of B. stearothermophilus, adopts two globally distinct native structures depending on the presence of monovalent cations. The structure under high ionic conditions (e100 mM) is 20% more compact as a result of a change in the relative orientation of the catalytic and specificity domains. This structure is well represented by the crystal structure. We also generate a molecular model for the structure under low ionic conditions structures that matches the molecular envelop obtained from the SAXS measurements. The agreement between the crystal structure and the models with the data is quantified using a cross-correlation function. Our results indicate that multi-domain RNAs can have more than one stable native structure. In the case of P RNA, these structures may be important in the assembly of the RNase P holoenzyme, a ribonucleoprotein particle.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 所有细菌RNase P RNA均由两个独立折叠域组成。这些结构域在芽孢杆菌的晶状体结构中相互堆积，并在硬化菌的RNase P RNA的晶体结构中。这种并排的堆积被广泛认为是唯一可以适应细菌PRNA的天然结构。在这里，我们使用小角度的X射线散射，在线探测和分子建模表明，枯草芽孢杆菌的P RNA是枯草芽孢杆菌的紧密同源物，根据单价阳离子的存在，采用了两种全球不同的天然结构。由于催化和特异性域的相对方向变化，高离子条件下（E100 mM）下的结构更加紧凑。这种结构由晶体结构很好地表示。我们还生成了一个在低离子条件结构下结构的分子模型，该结构与从SAXS测量结果获得的分子信封相匹配。晶体结构与模型与数据之间的一致性使用互相关函数进行量化。我们的结果表明，多域RNA可以具有多个稳定的天然结构。在P RNA的情况下，这些结构在RNase P Holoenzyme（核糖核蛋白颗粒）的组装中可能很重要。