Defining post-transcriptional gene regulation in FMRP-deficiency usingmiRNA:target chimeras

使用 miRNA：目标嵌合体定义 FMRP 缺陷的转录后基因调控

• 批准号: 10586591
• 负责人: MOLLIE Katherine MEFFERT
• 金额: $ 48.4万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-01 至 2027-11-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10586591
• 关键词: Affect; Behavioral; Binding Proteins; Biochemical; Biogenesis; Brain; Central Nervous System; Child; Chimera organism; Cognitive; Complex; Coupling; Data; Data Set; Detection; Development; Diagnostic; FMR1; Family; Fragile X Syndrome; Functional disorder; Gene Expression Regulation; Gene Targeting; Genes; Genetic Diseases; Goals; Growth; High-Throughput Nucleotide Sequencing; Human; Hyperactivity; Immunoprecipitation; Impairment; Incidence; Intellectual functioning disability; Intervention; Investigation; Knock-out; Knockout Mice; Knowledge; Ligation; Link; MAP Kinase Gene; MAPK3 gene; Mediating; Messenger RNA; MicroRNAs; Molecular; Molecular Target; Morphology; Motivation; Mus; Neuroanatomy; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neurons; Pathway interactions; Patients; Phenotype; Post-Transcriptional Regulation; Production; Protein Biosynthesis; Protein Deficiency; Proteins; RNA Binding; RNA-Binding Proteins; RNA-Induced Silencing Complex; Repression; Resistance; Signal Transduction; Small RNA; Social Interaction; Specificity; Synapses; Techniques; Testing; Time; Transcript; Translations; Untranslated RNA; Validation; autism spectrum disorder; behavioral phenotyping; brain abnormalities; cell type; cognitive function; crosslink; excitatory neuron; gene repression; genetic regulatory protein; genome-wide; human model; human stem cells; in vivo; induced pluripotent stem cell; interest; mouse model; nervous system disorder; neural; neuronal growth; posttranscriptional; programs; protein function; protein phosphatase inhibitor-2; repetitive behavior; restoration; social communication

Fragile X Syndrome (FXS) is the most common monogenic cause of Autism spectrum disorder (ASD), a group of complex neurodevelopmental disorders characterized by core diagnostic impairments in social interactions and communication, restricted repetitive behaviors and interests, and an association with intellectual disability. FXS results from deficiency in expression of the FMR1 gene encoding Fragile X Mental Retardation Protein (FMRP). An early overgrowth of neurons and excessive immature synaptic contacts have been observed in brains of children with FXS, as well as in the Fmr1 KO mouse model. At a molecular level, aberrant excessive protein synthesis, with altered production of key synaptic proteins, is implicated in the atypical neural and synaptic overgrowth. While FMRP loss can lead to excessive protein synthesis, mechanisms altering the gene-target selectivity of protein synthesis to produce the distinct phenotypes of FMRP-deficiency are incompletely understood. MicroRNAs (miRNAS) are small RNAs which can selectively target gene transcripts for repression in the RNA- induced silencing complex (RISC). FXS has been linked to misregulation of miRNAs and miRNA-mediated gene repression for over 15 years, but broad knowledge of alterations in targeted transcripts has been lacking. We propose to carry out genome-wide quantitative comparisons of RISC-mediated gene targeting in the wildtype and FMRP-deficient setting using both mice and human neurons. Directed by preliminary data, we will investigate the candidate let-7 miRNA family to test the hypothesis that dysregulation of let-7 miRNA biogenesis in the Fmr1 KO mouse contributes to altered repression of pro-growth mRNAs and downstream behavioral and neuroanatomical phenotypes. A multipronged approach for mechanistic investigation and prioritizing gene targets and pathways from genome-wide assessments will be followed by intervention to assess the functional consequences for FXS-associated phenotypes with the goal of enhancing our understanding of FMRP function and providing new molecular targets for intervention in phenotypes resulting from deficiency of FMRP.

脆性X综合征（FXS）是自闭症最常见的单基因原因 谱系障碍（ASD）是一组复杂的神经发育障碍 以社交互动中的核心诊断障碍为特征， 沟通，限制重复的行为和兴趣，以及协会 有智力障碍的人FXS由FMR 1表达缺陷引起 脆性X智力迟钝蛋白（FMRP）基因。早期过度生长 神经元和过度不成熟的突触接触已被观察到， FXS儿童的大脑，以及Fmr1 KO小鼠模型。在 分子水平，异常的过量蛋白质合成， 关键的突触蛋白，涉及非典型神经和突触过度生长。 虽然FMRP缺失可导致蛋白质合成过度，但机制改变 蛋白质合成的基因靶向选择性产生不同的表型 对FMRP缺陷的认识还不完全。microRNA（miRNAS）是一种小分子RNA。 可以选择性靶向基因转录物以抑制RNA中的RNA- 诱导沉默复合物（RISC）。FXS被认为与监管不当有关， miRNAs和miRNAs介导的基因抑制已经超过15年，但广泛 对靶向转录物中的改变缺乏了解。我们建议 进行RISC介导的基因打靶的全基因组定量比较 在野生型和FMRP缺陷的设置使用小鼠和人类神经元。 在此基础上，我们将对候选的let-7 miRNA家族进行研究 为了验证在Fmr1 KO中let-7 miRNA生物合成失调的假设， 小鼠有助于改变促生长mRNA和下游mRNA的抑制 行为和神经解剖表型。多管齐下的方法， 机制研究和优先考虑基因靶点和途径， 全基因组评估之后将进行干预，以评估功能性 FXS相关表型的后果，目的是提高我们的 了解FMRP的功能，并提供新的分子靶点， 干预FMRP缺乏导致的表型。