Antisense RNAs control retrotransposon copy number

反义 RNA 控制逆转录转座子拷贝数

• 批准号: 8686002
• 负责人: David J. Garfinkel
• 金额: $ 28.22万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8686002
• 关键词: AIDS/HIV problem; Acquired Immunodeficiency Syndrome; Address; Affect; Antisense RNA; Area; Behavior; Biochemical; Biochemical Genetics; Biological Assay; Biology; Biomedical Research; Cells; DNA Transposable Elements; Defect; Defense Mechanisms; Disease; Ectopic Expression; Evolution; Gene Expression; Genes; Genetic; Genetic Epistasis; Genetic Screening; Genetic Transcription; Genome; Goals; HIV; HIV-1; Health; Human; Human Genome; Induced Mutation; Integrase; Mediating; Messenger RNA; Modeling; Monitor; Mutation; Pathway interactions; Play; Process; Proteins; RNA; RNA Interference; RNA Sequences; RNA chemical synthesis; Relative (related person); Research; Resistance; Retrotransposition; Retrotransposon; Retroviridae; Retrovirology; Reverse Transcription; Role; Saccharomyces; Saccharomyces cerevisiae; Saccharomycetales; Structure; System; Transcript; Translations; Untranslated RNA; Virus; Virus-like particle; Work; base; combat; complement C2a; drug development; genetic analysis; human DICER1 protein; improved; insight; interest; mutant; novel

DESCRIPTION (provided by applicant): Antisense RNAs control retrotransposon copy number The retrovirus-like transposon Ty1 of Saccharomyces cerevisiae is an effective model for understanding the replication of HIV, the causative agent of AIDS, and is arguably the best understood retrotransposon. Retrotransposons replicate through an RNA intermediate and have colonized most eukaryotic genomes. Studying Ty1 has also provided valuable information on human genome dynamics and evolution, and the behavior of transposon-induced mutations. RNA interference (RNAi) is a widespread mechanism used to silence infectious viruses and transposable elements, and alter gene expression, where small sequence-specific RNAs and conserved cellular proteins affect transcription, degrade mRNA transcripts or inhibit translation. Interestingly, S. cerevisiae and its closest relatives lack the genes required for RNAi, yet maintain tight control over Ty1 retrotransposition. We discovered a copy number control (CNC) system based on Ty1 antisense (AS) RNAs that inhibits retrotransposition posttranslationally. The noncoding transcripts are packaged into virus- like particles and block reverse transcription by greatly decreasing the level of the conserved Ty1 protein integrase, which is required for Ty1 as well as HIV-1 reverse transcription and integration. Our goal is to understand the mechanism of this novel form of RNAi by 1) determining how Ty1AS transcripts inhibit retrotransposition, 2) identifying sequence domains that mediate Ty1AS RNA synthesis, packaging and activity within virus-like particles, and 3) characterizing cellular genes that influence AS transcript synthesis and function. We expect this study to impact two areas of biomedical research. First, understanding Ty1 CNC can be used to help elucidate the function of HIV noncoding RNAs, improve RNA-based therapies, and identify new targets for drug development. Second, our work will inform research addressing how noncoding RNAs impact human gene expression on a broader scale, especially when one considers that over 90% of the genome is transcribed, yet the function of many of these transcripts is poorly understood.

描述(申请人提供)：反义RNA控制反转录转座子拷贝数酿酒酵母的逆转录病毒样转座子Ty1是理解艾滋病的病原体HIV复制的有效模型，可以说是最了解的反转录转座子。反转录转座子通过一种RNA中间体进行复制，并在大多数真核基因组中定居。对Ty1的研究也为人类基因组动力学和进化以及转座子诱导突变的行为提供了有价值的信息。RNA干扰(RNAi)是一种广泛使用的机制，用于沉默感染性病毒和转座元件，改变基因表达，其中小序列特异性RNAs和保守的细胞蛋白影响转录，降解mRNA转录本或抑制翻译。有趣的是，酿酒酵母及其近亲缺乏RNAi所需的基因，但仍对Ty1逆转录转座保持严格控制。我们发现了一种基于Ty1反义(AS)RNA的拷贝数控制(CNC)系统，它可以抑制翻译后的逆转录转座。非编码转录本被包装成病毒样颗粒，通过大幅降低保守的Ty1蛋白整合酶水平来阻止逆转录，Ty1蛋白整合酶是Ty1以及HIV-1逆转录和整合所必需的。我们的目标是通过1)确定Ty1AS转录如何抑制逆转录转座，2)识别介导Ty1AS RNA合成、包装和病毒样颗粒内活性的序列结构域，以及3)表征影响转录产物合成和功能的细胞基因，来了解这种新型RNAi的机制。我们预计这项研究将影响生物医学研究的两个领域。首先，了解Ty1 Cnc有助于阐明HIV非编码RNA的功能，改进基于RNA的疗法，并确定药物开发的新靶点。其次，我们的工作将为研究非编码RNA如何在更广泛的范围内影响人类基因表达提供信息，特别是当人们考虑到超过90%的基因组是转录的，但其中许多转录本的功能却知之甚少。