RNA Binding Proteins in Complex Neurological Disease

复杂神经系统疾病中的 RNA 结合蛋白

• 批准号: 8858948
• 负责人: WAYNE N. FRANKEL
• 金额: $ 39.14万
• 依托单位: JACKSON LABORATORY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-02-01 至 2016-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8858948
• 关键词: Accounting; Action Potentials; Address; Adult; Animal Model; Animals; Autistic Disorder; Back; Behavior; Binding; Binding Sites; Brain; Brain Diseases; Cell Line; Cells; Central Nervous System Diseases; Cerebral cortex; Clustered Regularly Interspaced Short Palindromic Repeats; Complex; Cues; Cytoplasmic Granules; Data; Development; Disease; Dissection; Dose; Drosophila genus; Employee Strikes; Epilepsy; Equilibrium; Etiology; FMR1; FMRP; Failure; Family; Fragile X Mental Retardation Protein; Fragile X Syndrome; Functional disorder; Funding; Gene Expression Profile; Gene Targeting; Genes; Genetic; Genetic Translation; Genomic approach; Genotype; Hippocampus (Brain); Homeostasis; Human; Hyperactive behavior; Individual; Intellectual functioning disability; Ion Channel; Lead; Learning; Location; Membrane Potentials; Mental disorders; Messenger RNA; Metabolism; Mild obesity; Modeling; Molecular; Mus; Mutagenesis; Mutant Strains Mice; Mutate; Nature; Neurologic; Neurons; Neuropil; Neurotransmitter Receptor; Orthologous Gene; Outcome; Pathology; Patients; Pattern; Phenotype; Physiological; Polyribosomes; Predisposition; Proteins; RNA; RNA Binding; RNA-Binding Proteins; Recycling; Regulation; Research; Role; SCN8A gene; Schizophrenia; Seizures; Signal Transduction; Social Interaction; Sodium Channel; Sucrose; Symptoms; Synapses; Synaptic Vesicles; Synaptic plasticity; System; Testing; Transgenes; Translating; Translations; Untranslated Regions; Variant; Vision; Work; complex biological systems; density; disability; excitatory neuron; genetic variant; genome sequencing; in vivo; interest; member; mutant; nervous system disorder; neuron development; neuronal cell body; neuronal excitability; neurotransmission; non-genetic; particle; postnatal; programs; public health relevance; social; success; synaptic function; transcriptome sequencing

 DESCRIPTION (provided by applicant): Many factors make genetically complex diseases complex. Classically they are defined as an interaction between multiple genetic variants and non-genetic factors. Progress in genome sequencing and within-species variation has generated much interest in identifying polygenic variants from human and model organisms, with some success. But one cannot lose sight of the importance of physiological complexity; even Mendelian variants can wreak havoc when operating in a complex biological system. For functional phenotypes, such as excitability disorders of the CNS, this concept is understudied. Epilepsy is genetically complex to be sure, but as the canonical excitability disorder of the brain it also serves as a leading example for approaching other, harder-to-crack functional disorders, such as autism and schizophrenia, that are also likely to have excito-pathology at their cores. Neuronal excitability is determined primarily by molecules, such as ion channels and transporters, neurotransmitter receptors, and synaptic proteins, controlling membrane potential and synaptic signaling in order to achieve an appropriate balance of excitation and inhibition. Although cis-variants in genes encoding these molecules can lead to specific phenotypes, trans-factors that regulate their expression must be critical for maintaining this balance at a higher, coordinated level. We previously identified and characterized hypomorphic and null genotypes in Celf4 (formerly known as Brunol4), encoding a brain-specific member of the BRUNO/CUGBP/CELF family of RNA binding proteins. Celf4 mutants have a complex seizure disorder and other neurological phenotypes, such as hyperactivity, mild obesity and abnormal social interaction. Very recently human CELF4 deficiency revealed these and additional symptoms, such as intellectual disability. In our initial funding period, we found that CELF4 is most tightly associated with very high-density RNA granule particles and targets a vast number of mRNAs in excitatory neurons. Many targets are involved in synaptic functions, and they tend to be dysregulated within neurons of mutant mice - in all directions, but with a tendency towards increased expression away from the cell body. These findings are consistent with a role for CELF4 in control "translational silencing" perhaps at local, subcellular levels. We also obtained evidence for CELF4 effects on intrinsic neuronal hyperexcitation, via increased expression of sodium channel Nav1.6, and system-wide dysregulation via impaired homeostatic plasticity presumably due to dysregulation of synaptic proteins. Our hypothesis is that the combination of such effects accounts for full-blown disease. In the next 5 years, our research will address two prevailing themes that work together to address this idea. The first addresses the pattern of CELF4 binding motifs within the 3'-UTR of target mRNAs, and the consequences of altering the motifs on mRNA abundance, localization and translation, both transcriptome-wide and for selected targets. The second theme uses in vivo mutagenesis to assess the contribution of individual targets to the multigenic etiology of complex neurological phenotypes.

 描述（由申请人提供）：许多因素使遗传性复杂疾病变得复杂。传统上它们被定义为多种遗传变异和非遗传因素之间的相互作用。基因组测序和物种内变异的进展引起了人们对识别人类和模式生物的多基因变异的浓厚兴趣，并取得了一些成功。但我们不能忽视生理复杂性的重要性。在复杂的生物系统中运行时，即使是孟德尔变异也会造成严重破坏。对于功能表型，例如中枢神经系统兴奋性障碍，这个概念尚未得到充分研究。癫痫在遗传上确实很复杂，但作为典型的大脑兴奋性障碍，它也可以作为解决其他难以破解的功能障碍的主要例子，例如自闭症和精神分裂症，这些疾病的核心也可能是兴奋病理学。神经元兴奋性主要由离子通道和转运蛋白、神经递质受体和突触蛋白等分子决定，控制膜电位和突触信号传导，以实现兴奋和抑制的适当平衡。尽管编码这些分子的基因中的顺式变体可以导致特定的表型，但调节其表达的反式因子对于在更高、协调的水平上维持这种平衡至关重要。我们之前鉴定并表征了 Celf4（以前称为 Brunol4）的低效基因型和无效基因型，编码 RNA 结合蛋白 BRUNO/CUGBP/CELF 家族的大脑特异性成员。 Celf4突变体具有复杂的癫痫症和其他神经表型，例如多动、轻度肥胖和异常的社交互动。最近，人类 CELF4 缺乏症揭示了这些症状和其他症状，例如智力障碍。在我们最初的资助期间，我们发现 CELF4 与非常高密度的 RNA 颗粒紧密相关，并且靶向兴奋性神经元中的大量 mRNA。许多靶标与突触功能有关，并且它们在突变小鼠的神经元内往往在各个方向上失调，但有增加远离细胞体的表达的趋势。这些发现与 CELF4 可能在局部亚细胞水平上控制“翻译沉默”的作用一致。我们还获得了 CELF4 通过钠通道 Nav1.6 表达增加对内在神经元过度兴奋的影响，以及通过稳态可塑性受损（可能是由于突触蛋白失调）对系统范围内的失调产生影响的证据。我们的假设是，这些影响的结合导致了全面的疾病。在接下来的五年中，我们的研究将围绕两个共同的主题来解决这个想法。第一个解决了目标 mRNA 3'-UTR 内 CELF4 结合基序的模式，以及改变基序对 mRNA 丰度、定位和翻译的影响，包括转录组范围和选定目标。第二个主题使用体内诱变来评估单个靶标对复杂神经表型的多基因病因学的贡献。