STRUCTURE, MECHANISM AND CATALYSIS IN EVOLVED RIBOZYME AND RNA VIRUSES

该子项目是利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 我们正在研究催化RNA（或核酶）和来自病毒的RNA的结构。在SARS病毒RNA基因组的一个高度保守区域s2m RNA的最后一次射束时间分配期间，我们获得了新的晶体结构，该区域被认为对这种致病病毒的生命周期至关重要，是锤头状核酶的一种新结构（最初在各种植物卫星RNA病毒的背景下发现），以及体外进化的RNA连接酶的新结构，其催化被认为对于在前生物RNA世界中RNA自我复制的进化至关重要的反应。我们建议在下一个beamtime分配期间继续对所有三个RNA系统进行结构研究。具体而言，SARS s2m RNA结合肽和小分子的共晶体，以及SARS RNA/蛋白质复合物结构，将被解决，新的锤头状核酶结构的催化变体和突变体将被分析，并在体外进化的RNA连接酶的预连接状态将被获得。

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. We are investigating the structures of catalytic RNAs (or ribozymes) and RNAs derived from viruses. We have obtained new crystal structures during the last beamtime allocation period of a highly conserved region of the SARS virus RNA genome called the s2m RNA, thought to be critical to the life-cycle of this pathogenic virus, a new structure of the hammerhead ribozyme (originally discovered in the context of various plant satellite RNA viruses), and a new structure of an in vitro evolved RNA ligase that catalyzes a reaction thought to be of critical importance for the evolution of RNA selfreplication in a prebiotic RNA world. We propose to continue structural investigations of all three RNA systems during the next beamtime allocation period. Specifically, cocrystals of the SARS s2m RNA bound to peptides and small molecules, as well as SARS RNA/protein complex structures, will be solved, catalytic variants and mutants of the new hammerhead ribozyme structure will be analyzed, and a pre-ligation state of the in vitro evolved RNA ligase will be obtained.