Post-transcriptional gene regulation

转录后基因调控

• 批准号: 9977218
• 负责人: DAVID P BARTEL
• 金额: $ 71.29万
• 依托单位: WHITEHEAD INSTITUTE FOR BIOMEDICAL RES
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-05-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9977218
• 关键词: Area; Biochemical; Biochemical Genetics; Biogenesis; Biological Process; Cells; Cleaved cell; Complex; Congenital Abnormality; Coupling; Defect; Development; Disease; Embryo; Embryonic Development; Enzymes; Fertility; Gene Expression Regulation; Gene Silencing Pathway; Genes; Genetic Structures; Genetic Transcription; Human; Length; Malignant Neoplasms; Messenger RNA; Methods; MicroRNAs; Molecular; Molecular Computations; Pathway interactions; Patients; Play; Poly(A) Tail; Post-Transcriptional Regulation; Principal Investigator; Process; Proteins; RNA; RNA Interference; Regulation; Regulator Genes; Regulatory Pathway; Reporter Genes; Resources; Role; Small Interfering RNA; Structure; Tail; Transcript; Translational Repression; Untranslated RNA; Viral Cancer; Virus; Virus Diseases; Yeasts; Zebrafish; experimental study; gastrulation; gene function; genetic approach; human disease; improved; insight; mRNA Stability; novel therapeutics; programs; public health relevance; recruit

 DESCRIPTION (provided by applicant): Much of eukaryotic gene regulation occurs post-transcriptionally, through differential mRNA stability and/or translational efficiency. The researc of this proposal seeks to answer fundamental questions within three interrelated areas of post-transcriptional gene control: microRNAs, RNA interference, and mRNA poly (A) tails. MicroRNAs (miRNAs) are ~22-nt RNAs that pair to mRNAs to direct their destabilization and translational repression. More than 600 miRNA genes have been identified in humans, and because most human genes are conserved targets of miRNAs, it is no surprise that miRNAs play important roles in mammalian development and human diseases, including viral infections and cancers. Molecular, computational, and structural approaches will be used to determine 1) how the microRNA-biogenesis machinery recognizes the cellular transcripts that are to be processed into microRNAs, 2) the biochemical basis of miRNA-target recognition and improved methods for predicting the most repressed targets, 3) the reason that mRNAs from reporter genes are repressed differently than those from endogenous genes, and 4) the mechanism and the biological function of the regulation of a miRNA by a long noncoding RNA. Results of these studies are expected to enhance the fundamental understanding of this important class of gene-regulatory molecules and provide resources helpful for many biologists, including those studying the roles of miRNAs in human diseases. RNA interference (RNAi) is a gene-regulatory pathway that many eukaryotic species use to silence transposons and viruses. In this pathway, short interfering RNAs (siRNAs) resembling miRNAs are loaded into Argonaute, which is an effector protein that cleaves transcripts with extensive complementarity to the siRNA. Genetic, structural, biochemical, and molecular approaches will be used to 1) identify and study additional proteins required for efficient RNAi in yeast, 2) determine how the siRNA-Argonaute complex forms and how it recognizes mRNA targets, and 3) investigate the unusual activities of zebrafish Argonaute. Results are expected to provide mechanistic insight into this gene-silencing pathway fundamental for defending many eukaryotic species against transposons and viruses, with practical implications for biologists using this pathway to study gene function, as well as those harnessing it to treat patients. mRNA poly (A) tails are important for mRNA stability and translational efficiency, and metazoan miRNAs usually act by recruiting enzymes that shortening poly (A) tails. The relationship between poly (A)-tail length and translational efficiency changes as the embryo develops. Molecular, computational, biochemical, and genetic approaches will be used to determine how coupling between tail length and translational efficiency is established before gastrulation and why it disappears after gastrulation. Results are expected to provide fundamental insight into translational control and embryonic development, with potential implications for human fertility, developmental defects, or other diseases. OMB No. 0925-0001/0002 (Rev. 08/12 Approved Through 8/31/2015) Page Continuation Format Page

 描述（由申请人提供）：许多真核基因调控通过差异mRNA稳定性和/或翻译效率在转录后发生。本研究旨在回答转录后基因控制的三个相互关联的领域内的基本问题：microRNA，RNA干扰和mRNA poly（A）tail。微小RNA（microRNAs，miRNAs）是一种长度约为22个核苷酸的RNA，与mRNA配对，指导其去稳定化和翻译抑制。在人类中已经鉴定了600多个miRNA基因，并且由于大多数人类基因是miRNA的保守靶点，因此miRNA在哺乳动物发育和人类疾病（包括病毒感染和癌症）中发挥重要作用也就不足为奇了。分子、计算和结构方法将用于确定1）microRNA生物发生机制如何识别待加工成microRNA的细胞转录物，2）miRNA靶识别的生化基础和用于预测最受抑制的靶的改进方法，3）来自报告基因的mRNA与来自内源基因的mRNA不同地被抑制的原因，长链非编码RNA调控miRNA的机制和生物学功能。这些研究的结果有望增强对这类重要的基因调控分子的基本理解，并为许多生物学家提供有用的资源，包括那些研究miRNA在人类疾病中的作用的生物学家。RNA干扰（RNAi）是一种基因调控途径，许多真核生物使用它来沉默转座子和病毒。在该途径中，类似于miRNA的短干扰RNA（siRNA）被加载到Argonaute中，Argonaute是一种效应蛋白，其切割与siRNA具有广泛互补性的转录物。遗传、结构、生物化学和分子方法将用于1）鉴定和研究酵母中有效RNAi所需的其他蛋白质，2）确定siRNA-Argonaute复合物如何形成以及它如何识别mRNA靶标，3）研究斑马鱼Argonaute的异常活性。结果预计将提供对这种基因沉默途径的机制性见解，这是保护许多真核物种免受转座子和病毒侵害的基础，对生物学家使用这种途径研究基因功能以及利用它治疗患者具有实际意义。mRNA poly（A）尾对于mRNA的稳定性和翻译效率是重要的，并且后生动物miRNA通常通过募集缩短poly（A）尾的酶来起作用。poly（A）尾长度和翻译效率之间的关系随着胚胎发育而变化。分子，计算，生物化学和遗传学的方法将被用来确定如何连接尾长和翻译效率之间建立原肠胚形成前，以及为什么它消失原肠胚形成后。结果 有望为翻译控制和胚胎发育提供基本见解，对人类生育力，发育缺陷或其他疾病具有潜在意义。 OMB编号0925-0001/0002（2012年8月批准至2015年8月31日修订版）页码续页格式页码