Collaborative Research: RNA processing in trypanosome mitochondria

合作研究：锥虫线粒体中的 RNA 加工

• 批准号: 1616865
• 负责人: Jorge Cruz-Reyes
• 金额: $ 56.17万
• 依托单位: Texas A&M AgriLife Research
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-15 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1616865&HistoricalAwards=false
• 关键词: Collaborative; Research; RNA; processing; trypanosome

This project will study a unique mechanism of gene expression in ancient single-celled parasites called trypanosomes. Unlike most organisms that use the RNA copied from DNA "as is" for directing protein synthesis, in the energy-generating mitochondria of trypanosomes (and other organisms), the RNA is edited by addition or removal of specific information. Why editing occurs is not clear, but understanding how it happens may provide important clues about the function of this type of genetic alteration. The project will have broad educational impact by providing interdisciplinary training opportunities for postdoctoral, graduate, undergraduate, and high school students. In addition, specific efforts will target students from groups traditionally underrepresented in the STEM disciplines. This project focuses on the process of RNA editing in the mitochondria of trypanosomes. Through the action of a central editing enzyme, called RECC, uridylates are inserted or deleted at thousands of specific sites in dozens of mRNAs. This extensive editing process is directed by hundreds of small non-coding guide RNAs and involves several auxiliary factors. However, the mechanistic basis of the regulation of editing remains a long-standing question in trypanosomal RNA biology. In previous work, a regulatory editing subcomplex, called REH2C, was identified and found to contain three protein subunits. Two of these, a helicase and a zinc-finger protein, appear to participate directly in editing. A combination of genetic, biochemical, bioinformatics, and proteomic approaches will be used to address how these proteins assemble with mRNAs and guide mRNAs into editosome complexes in vivo and how the complexes carry out editing functions. These studies may establish new paradigms in RNA editing regulation. In a broader sense, the studies will allow a better understanding of how this amazing process evolved. This system can be used to draw analogies with related RNA helicases and RNA processes that are directed by small guide RNAs and that evolved more recently in eukaryotic lineages.

该项目将研究古代单细胞寄生虫锥虫基因表达的独特机制。与大多数使用从DNA“原样”复制的RNA来指导蛋白质合成的生物体不同，在锥虫（和其他生物体）的能量生成线粒体中，RNA是通过添加或删除特定信息来编辑的。基因编辑发生的原因尚不清楚，但了解它是如何发生的，可能会为了解这种基因改变的功能提供重要线索。该项目将为博士后、研究生、本科生和高中生提供跨学科的培训机会，具有广泛的教育影响。此外，还将针对传统上在STEM学科中代表性不足的群体的学生做出具体努力。本项目主要研究锥虫线粒体中的RNA编辑过程。通过一种被称为RECC的中心编辑酶的作用，尿苷酸在几十种mrna的数千个特定位点上被插入或删除。这种广泛的编辑过程由数百个小的非编码向导rna指导，并涉及几个辅助因素。然而，在锥虫RNA生物学中，编辑调控的机制基础仍然是一个长期存在的问题。在之前的工作中，一种被称为REH2C的调控编辑亚复合物被鉴定出来，并发现含有三个蛋白质亚基。其中两种，解旋酶和锌指蛋白，似乎直接参与编辑。将使用遗传、生化、生物信息学和蛋白质组学方法的组合来解决这些蛋白质如何与mrna组装并引导mrna进入体内的编辑体复合物以及这些复合物如何执行编辑功能。这些研究可能为RNA编辑调控建立新的范式。从更广泛的意义上说，这些研究将使我们更好地理解这个惊人的过程是如何演变的。该系统可用于与相关的RNA解旋酶和RNA过程进行类比，这些过程是由小向导RNA指导的，并且是最近在真核生物谱系中进化出来的。