Mechanism and functions of small RNA pathways in Neurospora

脉孢菌小RNA途径的机制和功能

• 批准号: 8503458
• 负责人: YI LIU
• 金额: $ 28.62万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8503458
• 关键词: Address; Adoption; Antiviral Agents; Biochemical; Biogenesis; Biological Models; Biological Process; DNA; DNA Damage; DNA Methylation; DNA biosynthesis; Development; Double-Stranded RNA; Enzymes; Eukaryota; Eukaryotic Cell; Exonuclease; Experimental Designs; Family; Foundations; Functional RNA; Gene Expression; Gene Expression Regulation; Gene Silencing; Generations; Genes; Genetic; Genome; Genomics; Goals; Human; Individual; Knowledge; Lead; Maintenance; Mediating; Messenger RNA; MicroRNAs; Molds; Neurospora; Neurospora crassa; Nucleotides; Organism; Pathway interactions; Pharmacologic Substance; Plants; Play; Process; Production; Protein Family; Proteins; RNA; RNA Interference; RNA Interference Pathway; RNA-Directed RNA Polymerase; Recombinant DNA; Ribonuclease III; Ribonucleases; Role; Route; Slice; Small Interfering RNA; Small RNA; Structure; System; Technology; Testing; Transcript; Transgenes; Validation; chromatin modification; design; fungus; gene discovery; gene function; homologous recombination; human DICER1 protein; human disease; member; novel; novel therapeutic intervention; pri-miRNA; public health relevance; therapeutic development; tool

DESCRIPTION (provided by applicant): RNA interference (RNAi) is a post-transcriptional/transcriptional gene silencing mechanism conserved from fungi to humans. In RNAi pathways, small non-coding RNAs (sRNAs) with sizes ranging from 20-30 nucleotides (nt), including microRNAs (miRNAs) and various small interfering RNAs (siRNAs), associate with and guide Argonaute family proteins to messenger RNA targets, resulting in the silencing of gene expression in diverse biological processes. The filamentous fungus Neurospora crassa, an organism that broadly employs gene silencing in regulation of gene expression, offers a unique and powerful system for understanding of RNAi pathways. We have previously established the biochemical mechanism for the dsRNA-induced activation of the RNAi pathway. By purifying the Argonaute QDE-2- associated sRNAs from Neurospora, we recently discovered three new types of sRNAs in this organism, including the DNA damage-induced qiRNA, first fungal miRNA-like sRNAs (milRNAs) and Dicer- independent small interfering RNAs (disiRNAs). Importantly, our studies demonstrated the existence of diverse sRNA biogenesis pathways in this organism, including Dicer-dependent and Dicer-independent mechanisms, and the roles of the Argonaute protein QDE-2 in sRNA biogenesis. In Specific Aim 1, we determine the mechanism of how DNA damage induces of qiRNA production and quelling. In Specific Aim 2, we will determine how different pri-milRNAs are processed into mature milRNAs by different pathways and will uncover the "design" principles that steer different milRNAs into different pathways. In Specific Aim 3, we will determine the biogenesis pathway and function of disiRNAs. Together, these studies address several fundamental questions in small RNA biogenesis and will expand our current knowledge of sRNA biogenesis pathways and sRNA function.

描述（由申请人提供）：RNA干扰（RNAI）是一种从真菌到人类保守的转录后/转录基因沉默机制。在RNAi途径中，尺寸为20-30个核苷酸（NT）的小型非编码RNA（SRNA），包括microRNA（miRNA）和各种小型干扰RNA（siRNAS），与Argonaute家族蛋白与Messenger RNA靶标有联系并指导基因生物学表达沉默。丝状真菌神经孢子虫是一种广泛采用基因沉默来调节基因表达的生物体，为理解RNAi途径提供了独特而强大的系统。我们以前已经建立了DSRNA诱导的RNAi途径激活的生化机制。通过净化来自Neurospora的Argonaute QDE-2-相关的SRNA，我们最近在该生物体中发现了三种新型的SRNA，包括DNA损伤诱导的QiRNA，第一个真菌miRNA样SRNA（MILRNAS）（MILRNA）和DICER-DICER-DICER- DICER-独立的小型干扰RNA（Disirirnas）。重要的是，我们的研究表明，在该生物体中存在多种SRNA生物发生途径，包括DICER依赖性和独立的机制，以及Argonaute蛋白QDE-2在SRNA生物发生中的作用。 在特定的目标1中，我们确定了DNA损伤如何诱导QIRNA产生和平移的机制。在特定的目标2中，我们将通过不同的途径确定如何将不同的PRI-MILRNA处理成成熟的MILRNA，并将发现将不同的Milrnas引导到不同途径的“设计”原理。在特定的目标3中，我们将确定disirnas的生物发生途径和功能。总之，这些研究解决了小RNA生物发生中的几个基本问​​题，并将扩大我们当前对SRNA生物发生途径和SRNA功能的知识。