STRUCTURE AND PHYSICAL PROPERTIES OF RNA

这个项目的目标是用核磁共振确定生物相关RNA和核糖核蛋白复合体的结构。它产生的信息将有助于更好地了解这些RNA参与的生物过程的化学基础，并将有助于存储有关RNA构象特性的现有信息，这些信息仍然知之甚少。由于RNA在基因表达的几乎每一个方面都扮演着关键的角色，这一知识对于理解人类的许多生理过程是基本的，无论是正常的还是病理的。本研究的第一个目标是：(1)大肠杆菌5S rRNA的环A区和螺旋II-III区；(2)核糖体蛋白L18及其与5S rRNA形成的复合体；(3)菠菜叶绿体5S rRNA的环E区。多年来，没有哪一种RNA的化学和酶方法比5S rRNA研究得更深入。除了为这一重要的核糖体成分提供结构外，这里提出的研究还使社区能够更好地理解5S rRNA上的化学探测数据，这应该使他们能够更准确地解释从结构确定较少的RNA获得的数据。叶绿体项目将阐明RNA中序列同源性的构象意义。在授权期晚些时候，将检查EBER II RNA及其与核糖体蛋白L22的复合体，以及酵母U2 SnRNA的环IIa/IIb区域的构象。与这些活动同时进行的还有旨在提高核糖核酸光谱分析人员质量的举措。其中最重要的是测量和使用残留偶极耦合数据来提高RNA溶液结构的远程精度，这是大分子核磁共振领域迅速发展的领域。

The objective of this project is the determination of the structures of biologically relevant RNAs and ribonucleoprotein complexes by NMR. The information it generates will lead to a better understanding of the chemical basis of the biological processes in which these RNAs participate, and will contribute to the store of information available about the conformational properties of RNA, which are still poorly understood. Since RNA plays a critical role in almost every aspect of gene expression, this knowledge is fundamental to understanding many physiological processes in humans, both normal and pathological. The first targets of this study will be: (1) the loop A and helix II-III domains of 5S rRNA from E. coli, (2) ribosomal protein L18 and the complex it forms with 5S rRNA, and (3) the loop E region from spinach chloroplast 5S rRNA. Over the years, no RNA has been studied more intensively by chemical and enzymatic means than that 5S rRNA. In addition to providing a structure for this important ribosomal component, the studies proposed here enable the community to better understand chemical probing data on 5S rRNA, and that should enable them to interpret more accurately data obtained from RNAs less amenable to structure determination. The chloroplast project will cast light on the conformational significance of sequence homology in RNA. Later in the grant period, EBER II RNA and its complex with ribosomal protein L22 will be examined, as will the conformation of the loop IIa/IIb region from yeast U2 snRNA. Running in parallel with these activities will be initiatives aimed at improving the quality of the structures RNA spectroscopists. The most important of these has to do with the measurement and use of residual dipolar coupling data to improve the long-range accuracy of RNA solution structures, which is rapidly developing area of the macromolecu1ar NMR field.