Tissue-specific regulation of RNA-based enzymes by their protein subunits

虽然大多数酶都是蛋白质，但也有一些被称为核酶的酶是含有蛋白质和RNA的多亚基复合物。 核酶通常催化细胞不能正确使用或继承遗传信息的基本过程。 该项目将研究两种不同的核酶，称为RNase P和RNase MRP。 它们的正常功能是修饰其他RNA分子，这些RNA分子本身对蛋白质合成至关重要。 这两种核酶都由多个蛋白质亚基和一个RNA分子组成。 拟议的工作将使用生物化学，遗传学和细胞生物学的组合，以确定每个蛋白质亚基的功能意义，重点是哺乳动物细胞。 这项工作的更广泛的影响包括更好地理解在所有细胞中发现的核酶。 该项目还旨在通过向研究生和一年级本科生提供指导研究经验，扩大对科学的参与，其中一些人来自科学、技术、工程和数学方面代表性不足的群体。 RNase P和MRP分别是tRNA和rRNA成熟所必需的核酸内切酶。RNase P和MRP的所有组分，包括催化RNA和几种相关蛋白质，被认为是生命所必需的，编码它们的基因突变可能导致疾病。然而，这些基于RNA的酶的蛋白质亚基的作用知之甚少。几个基本问题仍然悬而未决：单个亚基如何影响酶的功能？为什么在真核生物中有这么多的蛋白质亚基，而在细菌中只有一个？亚基变异体在动物中的作用是什么？这项研究将扩大我们对RNase P/MRP蛋白亚基的分子和细胞作用的理解，重点是它们的变体。一个特别的重点将是两个替代的亚基变体，显示组织特异性表达和非冗余的细胞功能。了解替代亚基组成如何允许后生动物RNase P和MRP的功能多样化将在生物科学中具有广泛的意义。这项研究由生物科学理事会分子和细胞生物科学部的遗传机制计划资助。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识产权进行评估来支持。优点和更广泛的影响审查标准。

Although most enzymes are proteins, there are a few, known as ribozymes, that are multi-subunit complexes containing both protein and RNA. Ribozymes typically catalyze essential processes without which cells could not use or inherit genetic information correctly. This project will investigate two different ribozymes known as RNase P and RNase MRP. Their normal function is to modify other RNA molecules that are themselves are essential for protein synthesis. Both of these ribozymes are comprised of multiple protein subunits and an RNA molecule. The proposed work will use a combination of biochemistry, genetics, and cell biology to ascertain the functional significance of each of the protein subunits, focusing on mammalian cells. The broader impacts of this work include better understanding of ribozymes found in all cells. The project also aims to broaden participation in science by providing mentored research experiences to graduate students and first-year undergraduates, some of whom are from groups under-represented in science, technology, engineering and mathematics. RNases P and MRP are essential endonucleases critical for maturation of tRNAs and rRNAs, respectively. All components of RNases P and MRP, including the catalytic RNA and several associated proteins, are considered essential for life, and mutations in the genes encoding them can cause disease. Nevertheless, the roles of the protein subunits of these RNA-based enzymes are poorly understood. Several fundamental questions remain open: How do individual subunits impact enzymatic function? Why are so many protein subunits found in eukaryotes but just one in bacteria? What are the roles of subunit variants in animals? This study will expand our understanding of the molecular and cellular roles of RNase P/MRP protein subunits by focusing on their variants. A particular emphasis will be on two alternative subunit variants that display tissue-specific expression and non-redundant cellular functions. Understanding how alternative subunit composition might allow for functional diversification of metazoan RNases P and MRP will be of widespread significance across biological sciences.This research is funded by the Genetic Mechanisms program in the Division of Molecular and Cellular Biosciences in the Directorate of Biological Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.