The Regulation of Neuronal Exon Splicing

选择性前信使RNA剪接是真核基因调控的一种重要手段， 基因产生各种mRNA和蛋白质。许多蛋白质对神经元发育和 活性通过替代外显子的差异包含而在功能上多样化。尽管其 虽然选择性剪接对神经元功能和疾病的重要性，但控制选择性剪接的机制很差， 明白我们建议继续我们的研究神经元外显子剪接的重点是四个调控 proteins.多聚嘧啶道结合蛋白（PTB）及其神经元同源物nPTB是剪接阻遏物 多个外显子。Fox-1和Fox-2蛋白是一组不同但重叠的外显子的增强子。 以前，在体外重建的神经元特异性N1外显子的c-src的调节。我们将使用这个 系统来分析PTB如何抑制剪接体组装，并鉴定其靶相互作用。神经元 PTB不抑制N1和其他神经元外显子的剪接。实验将研究这种高度 同源蛋白质活性不同。Fox蛋白通过激活N1和其他神经元外显子， 重要剪接增强子元件UGCAUG。这种剪接刺激的机制将被检查 使用体外和体内方法。这些调节器在分化神经元中的生物学将是 通过它们在细胞中的缺失或错误表达来探索。由这些因素控制的外显子组将 在微阵列实验中被鉴定，并检查共同特征和共同功能 调控途径。在神经元和胶质细胞中，PTB对nPTB的复杂转录后调节将 也是一个焦点。通过这些实验，我们希望了解这些蛋白质的作用机制， 作用，以及它们在神经元细胞生物学中的作用。 理解选择性剪接对于我们理解多种形式的遗传学是至关重要的。 疾病脊髓性肌萎缩症、强直性肌营养不良症和前额叶痴呆是神经系统疾病， 剪接调控许多人类疾病突变改变剪接调控元件以产生异常的 proteins.为了治疗这些疾病，需要更多关于 剪接调控机制及其在神经元功能中的作用。

Alternative pre-messenger RNA splicing is a critical means of eukaryotic gene regulation that allows a single gene to produce a variety of mRNAs and proteins. Many proteins important for neuronal development and activity are functionally diversified through the differential inclusion of alternative exons. In spite of its importance to neuronal function and disease, the mechanisms controlling alternative splicing are poorly understood. We propose to continue our studies of neuronal exon splicing with a focus on four regulatory proteins. Polypyrimidine Tract Binding Protein (PTB) and its neuronal homolog nPTB are splicing repressers for multiple exons. The Fox-1 and Fox-2 proteins are enhancers of a different but overlapping set of exons. Previously, the regulation of the neuron-specific N1 exon of c-src was reconstructed in vitro. We will use this system to analyze how PTB represses spliceosome assembly, and identify its target interactions. Neuronal PTB does not repress the splicing of N1 and other neuronal exons. Experiments will examine how this highly homologous protein differs in activity. The Fox proteins activate N1 and other neuronal exons through an important splicing enhancer element UGCAUG. The mechanism of this splicing stimulation will be examined using both in vitro and in vivo approaches. The biology of these regulators in differentiating neurons will be explored through their depletion or mis-expression in cells. Groups of exons controlled by these factors will be identified in microarray experiments and examined for common features and function in common regulatory pathways. The complex posttranscriptional regulation of nPTB by PTB in neurons and glia will also be a focus. Through these experiments, we hope to understand both the mechanisms of these proteins' action, and the role they play in neuronal cell biology. The understanding of alternative splicing is essential to our understanding of multiple forms of genetic disease. Spinal Muscular Atrophy, Myotonic Dystrophy, and Prefrontal Dementia are neurologic disorders of splicing regulation. Many human disease mutations alter splicing regulatory elements to produce aberrant proteins. For these diseases to be approached therapeutically, much more information is needed on the mechanisms of splicing regulation and its role in neuronal function.