Identification of nanos mRNA localizatino factors in Drosophila

果蝇纳米mRNA定位因子的鉴定

• 批准号: 7611407
• 负责人: Kristina Sutphen Sinsimer
• 金额: $ 4.72万
• 依托单位: PRINCETON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-02-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7611407
• 关键词: 3' Untranslated Regions; Affinity Chromatography; Anterior; Binding; Binding Proteins; Binding Sites; Biochemical; Cells; Cis-Acting Sequence; Complex; Coupled; Data; Defect; Development; Disease; Drosophila genus; Elements; Embryo; Embryonic Development; Ensure; Eukaryotic Cell; Gene Expression; Genetic; Goals; Homologous Gene; Investigation; Lead; Malignant Neoplasms; Mediating; Messenger RNA; Methods; Oocytes; Ovarian; Process; Proteins; RNA; RNA-Binding Proteins; Regulation; Ribonucleoproteins; Role; Signal Transduction; Trans-Activators; Translational Repression; Translations; Work; insight; prevent; protein complex; protein expression; research study

DESCRIPTION (provided by applicant): Intracellular mRNA localization is a conserved mechanism for generating asymmetry in eukaryotic cells. Localization of nanos (nos) mRNA at the posterior pole of the Drosophila oocyte, and its subsequent translation, is critical for embryonic anterior-posterior axis formation and for establishment of a functional germline. Posterior localization is directed by a cis-acting signal in the nos 3'UTR comprising multiple, partially functional elements. Previous studies suggest that trans-acting factors bind to this localization signal to package nos RNA into a ribonucleoprotein (RNP) complex that permits localization. However, only one nos localization factor, the Drosophila heterogeneous ribonucleoprotein (hnRNP) M homolog, Rumpelstiltskin (Rump), has been identified thus far. Furthermore, nos localization must be tightly coupled with translational control to ensure posterior expression of Nos protein. This is achieved by another cis- acting sequence that contains binding sites for ovarian and embryonic translational repressers. Together, these repressers prevent expression of unlocalized nos mRNA. It is currently unknown how nos mRNA is coordinately regulated by localization factors and translational repressers. The goal of this work is to determine how mRNA localization signals are recognized by components of the cellular localization machinery and how the interaction of RNA-binding proteins with these signals direct RNA localization. Preliminary results identify a role for a second protein, Lost, in nos localization, and establish both genetic and biochemical interactions between Lost and Rump. These results prompt further investigations that will determine if Lost acts indirectly or directly to regulate nos localization, and will evaluate the interaction of Lost with Rump and potentially, translational control factors. Eliminating Lost and Rump does not completely abolish nos localization, likely due to functional redundancy in the nos localization signal. This result motivates the second aim of this proposal, to identify additional factors that interact with the nos mRNA localization signal and contribute to the regulation of mRNA localization and translation. Together, these experiments will allow us to determine how mRNAs are packaged for intracellular localization and how RNA localization and translational control are coordinately regulated. Abnormal expression of the proteins that control embryonic development is associated with a number of diseases. By understanding the mechanisms by which cells regulate gene expression during development, the proposed work will provide insight as to how defects in normal processes lead to diseases such as cancer.

描述（由申请人提供）：细胞内mRNA定位是真核细胞中产生不对称性的保守机制。果蝇卵母细胞后极的 nanos (nos) mRNA 定位及其随后的翻译对于胚胎前后轴的形成和功能性种系的建立至关重要。后定位由包含多个部分功能元件的 nos 3'UTR 中的顺式作用信号引导。先前的研究表明，反式作用因子与该定位信号结合，将 nos RNA 包装成允许定位的核糖核蛋白 (RNP) 复合物。然而，迄今为止，仅鉴定了一种 nos 定位因子，即果蝇异质核糖核蛋白 (hnRNP) M 同源物 Rumpelstiltskin (Rump)。此外，nos 定位必须与翻译控制紧密结合，以确保 Nos 蛋白的后表达。这是通过另一个包含卵巢和胚胎翻译抑制子结合位点的顺式作用序列来实现的。这些阻遏物共同阻止未定位的 nos mRNA 的表达。目前尚不清楚 nos mRNA 如何受到定位因子和翻译抑制子的协调调节。这项工作的目标是确定细胞定位机制的组件如何识别 mRNA 定位信号，以及 RNA 结合蛋白与这些信号的相互作用如何指导 RNA 定位。初步结果确定了第二种蛋白质 Lost 在 nos 定位中的作用，并建立了 Lost 和 Rump 之间的遗传和生化相互作用。这些结果促使进一步的调查，以确定 Lost 是否间接或直接调节 nos 本地化，并将评估 Lost 与臀部的相互作用以及潜在的翻译控制因素。消除 Lost 和 Rump 并不能完全消除 nos 定位，这可能是由于 nos 定位信号中的功能冗余。这一结果激发了该提案的第二个目标，即确定与 nos mRNA 定位信号相互作用并有助于 mRNA 定位和翻译调节的其他因素。总之，这些实验将使我们能够确定 mRNA 如何包装以进行细胞内定位，以及 RNA 定位和翻译控制如何协调调节。控制胚胎发育的蛋白质的异常表达与许多疾病有关。通过了解细胞在发育过程中调节基因表达的机制，拟议的工作将提供有关正常过程的缺陷如何导致癌症等疾病的见解。