GROUP I RIBOZYME P4-P6 DOMAIN FROM TETRAHYMENA

这个子项目是许多利用 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来源获得了主要资金， 因此可在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 I组内含子"或核酶"是独立折叠的RNA分子，其可以在翻译之前从信使RNA（mRNA）自我剪接。自25年前发现以来，已经鉴定了超过2000个I组内含子序列。根据序列和二级结构保守性将这些核酶分为不同的亚类。第一个晶体结构域（160个核苷酸;非催化）的第一组核酶从四膜虫的纤毛虫嗜热在1996年获得。在2001年获得了含有单核苷酸变化的突变体的改进的分辨率。 在这个项目中，我们首先获得了P4-P6结构域和特异性结合配体之间的复合物的晶体。我们的希望是，高分辨率的复合物结构将有助于我们理解小分子与其RNA靶标之间的分子识别。 其次，我们进一步突变了原始RNA构建体，以寻求进一步提高分辨率。目前正在筛选这些构建体用于结晶。这种方法可以为将来设计用于晶体学的RNA构建体提供一般指导。

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. Group I introns ¿¿¿¿¿"or ribozymes¿¿¿¿¿" are independently folded RNA molecules that can self-splice from a messenger RNA (mRNA) prior to translation. More than 2000 sequences of group I introns have been identified since their discovery ~25 years ago. These ribozymes were classified into different subgroups based on sequence and secondary structure conservation. The first crystal structure of a domain (160 nucleotides; non-catalytic) from a group I ribozyme from the ciliate Tetrahymena thermophila was obtained in 1996. Improved resolutions were obtained in 2001 for a mutant containing a single nucleotide change. In this project, we first obtained crystals of a complex between the P4-P6 domain and a specifically bound ligand. Our hope is that a structure of that complex at high resolution would facilitate our understanding of the molecular recognition between a small molecule and its RNA target. Second, we further mutated the original RNA construct in order to seek for further improvement of resolution. These constructs are being currently screened for crystallization. This approach could offer general guidelines for the future design of RNA constructs for crystallography.