Investigation of Fragile X mental retardation protein interactions with the miRNA pathway.

脆性 X 智力迟钝蛋白与 miRNA 通路相互作用的研究。

• 批准号: 9303733
• 负责人: MIHAELA R MIHAILESCU
• 金额: $ 41.4万
• 依托单位: DUQUESNE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2021-09-20
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9303733
• 关键词: Affect; Affinity; Alternative Splicing; Arginine; Binding; Binding Sites; Biochemical; Biogenesis; Biological Process; Complex; Development; Dicer Enzyme; Event; Exons; FMR1; Female; Fragile X Syndrome; G-Quartets; GTP-Binding Protein alpha Subunits, Gs; GTP-Binding Proteins; Glycine; Goals; Guide RNA; Impairment; Inherited; Investigation; KH Domain; Knowledge; Laboratories; Length; Mental Retardation; Messenger RNA; MicroRNAs; Molecular; Molecular Chaperones; Names; Nucleic Acids; Nucleotides; Pathway interactions; Phenotype; Phosphorylation; Play; Process; Production; Protein Biosynthesis; Protein Isoforms; Proteins; Psyche structure; RNA; RNA Interference; RNA Sequences; RNA-Binding Proteins; RNA-Induced Silencing Complex; Regulation; Research; Role; SUI1 gene; Site; Specificity; Structure; Synapses; Syndrome; Testing; Translations; Untranslated RNA; Work; male; novel; response

Project Summary Fragile X mental retardation syndrome is the most common form of inherited mental retardation, affecting ~ 1 in 3600 males and ~ 1 in 6000 females. The syndrome is caused by the loss of a normal cellular protein, named the fragile X mental retardation protein (FMRP). Despite extensive research in the past two decades, the relationship between the absence of FMRP and the phenotype of the fragile X syndrome is still not fully understood. FMRP is an RNA binding protein involved in the transport and translation regulation of specific messenger RNA (mRNA) targets. Biochemical studies have determined that FMRP uses its arginine-glycine- glycine (RGG) box to bind with high affinity to RNA sequences that form G quadruplex (GQ) structures. The mechanisms by which FMRP exerts its translation regulator function are not known, however it has been proposed that the protein works in conjunction with the microRNA (miRNA) pathway to regulate local protein synthesis in response to synaptic input. This proposal has the following specific aims: 1. Investigation of the FMRP role in miRNA maturation. Several miRNAs have been shown to require FMRP to exert their function, and FMRP has also been shown to bind pre-miRNAs. We hypothesize that FMRP regulates the maturation of specific miRNAs through its interactions with GQ structures formed by their precursor pre-miRNAs. To test this hypothesis we will characterize the GQ structures predicted to form in selected pre-miRNAs and analyze their interactions with FMRP. Subsequently, we will analyze the effect of FMRP upon the production of mature miRNAs by Dicer. 2. Investigation of FMRP: GQ mRNA: miRNA interactions in translation regulation. FMRP has been shown to directly regulate the translation of specific mRNAs through its interactions with the miRNA-guided RNA induced silencing complex (RISC). Following the guiding hypothesis that FMRP interacts with GQ structures in specific mRNAs to modulate their recognition by RISC, under this aim we will analyze FMRP: GQ mRNA: miRNA interactions in the context of other mRNAs that have predicted GQ structures: (i) within their miRNA binding sites and (ii) immediately adjacent to them. 3. Investigation of various FMRP isoforms interactions with the miRNA pathway. We hypothesize that the FMRP isoforms created by alternative splicing at exon 12 will have different interactions with miRNA precursors and/or protein components of the miRNA pathway, which could potentially result in functional differences with respect to translation regulation. Additionally, we hypothesize that FMRP activity-dependent primary and secondary phosphorylation events could further modulate these functional differences.

项目概要 脆性 X 智力低下综合征是遗传性智力低下最常见的形式，影响 ~ 1 3600 名男性和约 6000 名女性中 1 人。该综合征是由于正常细胞蛋白质的丢失引起的， 命名为脆性X智力低下蛋白（FMRP）。尽管过去二十年进行了广泛的研究， FMRP 缺失与脆性 X 综合征表型之间的关系尚不完全 明白了。 FMRP 是一种 RNA 结合蛋白，参与特定分子的转运和翻译调节。 信使 RNA (mRNA) 目标。生化研究已确定 FMRP 使用其精氨酸-甘氨酸- 甘氨酸 (RGG) 盒以高亲和力与形成 G 四链体 (GQ) 结构的 RNA 序列结合。这 FMRP 发挥其翻译调节功能的机制尚不清楚，但已被证实 提出该蛋白质与 microRNA (miRNA) 途径协同作用来调节局部蛋白质 响应突触输入的合成。该提案有以下具体目标： 1. FMRP 在 miRNA 成熟中的作用研究。一些 miRNA 已被证明需要 FMRP 发挥其功能，并且 FMRP 也已被证明可以结合 pre-miRNA。我们假设 FMRP 通过与 miRNA 形成的 GQ 结构相互作用来调节特定 miRNA 的成熟。 前体 pre-miRNA。为了检验这个假设，我们将描述预计形成的 GQ 结构 选择 pre-miRNA 并分析它们与 FMRP 的相互作用。接下来我们来分析一下效果 FMRP 基于 Dicer 生产成熟 miRNA。 2. FMRP 的研究：GQ mRNA：翻译调控中的 miRNA 相互作用。 FMRP已显示 通过与 miRNA 引导的 RNA 相互作用，直接调节特定 mRNA 的翻译 诱导沉默复合物（RISC）。遵循 FMRP 与 GQ 结构相互作用的指导假设 特定的 mRNA 来调节 RISC 对其的识别，在此目标下，我们将分析 FMRP：GQ mRNA： 与其他已预测 GQ 结构的 mRNA 背景下的 miRNA 相互作用：(i) 在其 miRNA 内 结合位点和 (ii) 紧邻它们。 3.研究各种FMRP亚型与miRNA途径的相互作用。我们假设 外显子 12 处选择性剪接产生的 FMRP 同工型将与 miRNA 产生不同的相互作用 miRNA 途径的前体和/或蛋白质成分，这可能会导致功能性 翻译监管方面的差异。此外，我们假设 FMRP 活动依赖 初级和次级磷酸化事件可以进一步调节这些功能差异。