Structural and functional studies of RNase MRP RNP

项目摘要 本项目致力于核糖核酸酶(RNase)MRP的结构和功能研究。RNase MRP和 必需的和通用的真核细胞特异性内切核糖核酸酶。它是一种450 kDa的多组分催化剂 核糖核蛋白(RNP)与核糖核酸酶P相关，但它已进化为具有明显的底物特异性和 独特的细胞功能。核糖核酸酶MRP参与多种RNA分子的新陈代谢， 包括rRNA和一些mRNA。在人类中，RNase MRP活性的改变会导致一系列 发育障碍，通常导致极短的身材，脆弱的头发，易患上 癌症和其他异常；导致这些问题的机制并不被称为核糖核酸酶MRP 仍然没有得到充分的研究。 这项建议的具体目标是： 1.冷冻法测定酿酒酵母核糖核酸酶MRP全酶的结构组织 电子显微镜(冷冻-EM)。 2.酵母核糖核酸酶MRP与底物相互作用的研究 这一提议将揭示RNaseMRP的结构及其与其RNaseP前体的差异。会的 揭示RNase、MRP、RNA和蛋白质在与不同范围的 底物，并阐明核糖核酸酶MRP底物识别和切割位点选择的机制， 为RNase MRP细胞功能的表征铺平了道路。这些研究将具有广泛的 通过揭示RNase MRP/P领域中蛋白质和RNA之间的相互作用 通过促进我们对RNP的结构、功能和进化的理解 催化RNPs。

Project Summary This project is focused on structural and functional studies of Ribonuclease (RNase) MRP. RNase MRP an essential and universal site-specific eukaryotic endoribonuclease. It is a 450 kDa multicomponent catalytic ribonucleoprotein (RNP) related to RNase P, but it has evolved to have a distinct substrate specificity and unique cellular functions. RNase MRP is involved in the metabolism of a wide range of RNA molecules, including rRNA and some mRNAs. In humans, altered RNase MRP activity results in a range of developmental disorders that typically lead to an extremely short stature, brittle hair, predisposition to cancers, and other abnormalities; the mechanisms causing these problems are not known as RNase MRP remains understudied. The specific aims of the proposal are: 1. Determination of the structural organizations of the S. cerevisiae RNase MRP holoenzyme using cryo- electron microscopy (cryo-EM). 2. Characterization of interactions of yeast RNase MRP with its substrates. This proposal will reveal the structure of RNase MRP and its divergence from its RNase P progenitor. It will uncover the respective roles of RNase MRP RNA and proteins in the interactions with a diverse range of substrates and clarify the mechanisms of RNase MRP substrate recognition and cleavage site selection, paving the way to the characterization of RNase MRP cellular functions. These studies will have a broad impact beyond the RNase MRP/P field by revealing the interplay of proteins and RNA in one of the most complex RNP enzymes, and by advancing our understanding of the structure, function, and evolution of catalytic RNPs.