Functional analysis of microRNA genes in Drosophila

果蝇microRNA基因的功能分析

• 批准号: 6843745
• 负责人: Victor Ambros
• 金额: $ 27.95万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-02-01 至 2008-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6843745
• 关键词: Caenorhabditis elegans; Drosophilidae; RNA; biological signal transduction; ecdysone; functional /structural genomics; gene expression; gene mutation; genetic regulation; genetic translation; green fluorescent proteins; messenger RNA; northern blottings; polymerase chain reaction; posttranslational modifications

DESCRIPTION (provided by applicant): The small regulatory RNA products of the lin-4 and let-7 genes of C. elegans are microRNAs (miRNAs) that control developmental timing in worm larvae. lin-4 and let-7 function by repressing the translation of specific target messenger RNAs via RNA: RNA antisense base-pairing. lin-4, let-7 and certain other miRNAs are evolutionarily conserved among worms, insects and vertebrates, and in some cases, homologs are expressed in similar profiles in diverse animals. These conserved microRNAs may play similar roles in the post-transcriptional control of gene expression during development of vertebrates and invertebrates. This project is designed to determine the in vivo function of four developmentally regulated, evolutionarily conserved, microRNAs in Drosophila melanogaster, let-7, mir-34, mir-100, and mir-125 (the fly ortholog of lin-4). The let-7, mir-125 and mir-100 genes are clustered in the Drosophila genome, and are up-regulated by ecdysone signaling in conjunction with a major developmental transition in flies, larva-to-adult metamorphosis. By contrast, mir-34 expression is down-regulated by ecdysone at the onset of metamorphosis. The goals of this project are to 1) isolate loss-of-function mutations in let-7, mir-125, mir-100, and mir-34, and analyze any resulting defects in fly development; 2) determine the temporal and spatial patterns of expression of let-7, mir-125, mir-100, and mir-34 during Drosophila development; 3) analyze developmental defects resulting from the over-expression and ectopic expression of these miRNAs; 4) identify messenger RNAs that are antisense targets of let-7, mir-125, mir-100, and mir-34; 5) identify additional evolutionarily conserved miRNA genes that are activated or repressed by ecdysone signaling during Drosophila development. This project will exploit Drosophila genetics to define the biological processes that evolutionarily conserved miRNAs control and will illuminate molecular mechanisms fundamental to animal development, including mammals, and insects significant to human health.

描述（由申请人提供）： 秀丽隐杆线虫的Lin-4和Let-7基因的小调节RNA产物是控制蠕虫幼虫中发育时机的microRNA（miRNA）。 LIN-4和LET-7通过通过RNA抑制特定靶标的RNA的翻译来函数：RNA反义碱基对。 LIN-4，Let-7和某些其他miRNA在蠕虫，昆虫和脊椎动物中是进化保守的，在某些情况下，同源物在不同动物的相似特征中表达。这些保守的microRNA可能在脊椎动物和无脊椎动物发育过程中基因表达的转录后控制中起着相似的作用。该项目旨在确定果蝇果蝇中的四个发育调节，进化保守的microRNA的体内功能，let-7，miR-34，miR-100和miR-125（LIN-4的蝇源性直立性）。 Let-7，miR-125和miR-100基因聚集在果蝇基因组中，并通过ecdysone信号传导与苍蝇的主要发育过渡，幼虫到种类变质的主要发育过渡。相比之下，在变形时，miR-34的表达被ecdysone下调。该项目的目标是1）在let-7，miR-125，miR-100和miR-34中隔离功能丧失突变，并分析苍蝇发育中任何结果的缺陷； 2）确定果蝇发育过程中Let-7，miR-125，miR-100和miR-34表达的时间和空间模式； 3）分析这些miRNA的过表达和异位表达产生的发育缺陷； 4）确定是let-7，miR-125，miR-100和miR-34的反义靶标的信使RNA； 5）确定果蝇发育过程中ecdysone信号传导激活或抑制的其他进化保守的miRNA基因。该项目将利用果蝇遗传学来定义生物学过程，即进化保守的miRNA控制，并将阐明对动物发育基础的分子机制，包括哺乳动物，昆虫对人类健康意义重大。