Biophysical studies of H/ACA snoRNAs and psi in rRNA

rRNA 中 H/ACA snoRNA 和 psi 的生物物理学研究

• 批准号: 0419068
• 负责人: Edward Nikonowicz
• 金额: $ 47.21万
• 依托单位: William Marsh Rice University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0419068&HistoricalAwards=false
• 关键词: Biophysical; studies; ACA; snoRNAs; psi

The long-term goal of this project is to understand key aspects of the post-transcriptional modification process of pre-ribosomal RNA (pre-rRNA) at the molecular level, including the basis of molecule specific RNA recognition by modification enzymes and the functional basis for modifications within RNA molecules. This research focuses on pseudouridine modification sites within eukaryotic rRNA and the small nucleolar ribonucleoprotein particles (snoRNPs) that introduce them. The project will explore the interaction of snoRNP proteins with their RNA ligand, and examine the thermodynamic and structural effects of snoRNA-mediated selection of pseudouridylation sites in functionally important regions of the eukaryotic large subunit rRNA using biochemical methods and high resolution NMR spectroscopy as the principal tools. Specifically, the following topics will be addressed: (1) structural and thermodynamic studies of snoRNA-rRNA complexes and (2) comparative structural and thermodynamic studies of the unmodified and pseudouridyl-modified forms of the eukaryotic large subunit rRNA. The results of these studies are directly relevant to understanding the specificity and affinity of protein-RNA interactions and the mechanisms used by RNA molecules to tweak local conformation and stability. These investigations complement genetic studies of the pseudouridylation reactions catalyzed by the snoRNPs and together provide a route to understanding the functional roles of the most common and phylogenetically conserved RNA base modification. The methods developed during these studies will serve as tools for structural biologists and chemical biologists.

该项目的长期目标是了解分子水平上的核糖体RNA（rRNA）的转录后修饰过程的关键方面，包括通过修饰酶的分子特异性RNA识别的基础和RNA分子内修饰的功能基础。这项研究的重点是真核rRNA中的假性修饰位点和引入它们的小核仁核糖核蛋白颗粒（SNORNP）。该项目将探索snORNP蛋白与其RNA配体的相互作用，并使用生物核心大量亚基RRNA的功能重要区域中SNORNA介导的伪源性基位点选择的热力学和结构效应，并使用生物学方法和高分辨率NMR NMR光谱工具（如原理工具）。具体而言，将解决以下主题：（1）SNORNA-RRNA复合物的结构和热力学研究以及（2）真核大型亚基RRNA的未修饰和假尿素改性形式的比较结构和热力学研究。这些研究的结果与了解蛋白-RNA相互作用的特异性和亲和力以及RNA分子使用以调整局部构象和稳定性的机制直接相关。这些研究补充了snornps催化的假胞苷化反应的遗传研究，并共同提供了一种理解最常见和最常见和系统发育保守的RNA碱基修饰的功能作用的途径。这些研究期间开发的方法将作为结构生物学家和化学生物学家的工具。