NERVE GROWTH FACTOR SIGNALING

神经生长因子信号传导

• 批准号: 6484969
• 负责人: MARIE W WOOTEN
• 金额: $ 5万
• 依托单位: AUBURN UNIVERSITY AT AUBURN
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6484969
• 关键词: PC12 cells; binding sites; cell cycle proteins; ceramides; enzyme activity; enzyme mechanism; growth factor receptors; guanine nucleotide binding protein; immunoprecipitation; isozymes; neurogenesis; neurotrophic factors; phosphorylation; protein kinase C; protein localization; protein protein interaction; protein signal sequence; protein tyrosine kinase; protooncogene; second messengers; site directed mutagenesis; transfection

DESCRIPTION (Adapted from applicant's abstract): Atypical PKC isoforms (iota/zeta) have been shown to play a critical role in regulation of various neuronal processes including, differentiation, survival and long-term potentiation. In PC-12 cells a PKCs, as well as their second messenger activator, P13 polyphosphoinositides, are required for both differentiation and survival responses. We have recently shown that aPKCs are tyrosine phosphorylated in response to nerve growth factor (NGF). ZIP/p62 and Par4 are binding proteins that regulate the localization and activation of aPKCs. Preliminary studies document an NGF receptor-regulated phosphotyrosine dependent interaction of src with sPKC. We hypothesize that tyrosine phosphorylation of atypical PKC by src moduates activity, as well as, its ability to interact with its protein regulators, Par4 and ZIP. Therefore, one specific aim is to study the mechanisms by which aPKC-iota is regulated by tyrosine phsophorylation to include regulation by NGF receptor components, p75 and TrkA, as well as, second messenger. A second aim is to unravel the mechanismwhereby aPKC is regulated by src kinase to include regulation of aPKC localization, signal-complex formation and interaction with protein regulators, as well as to examine the specific tyrosine residues that regulate NGF/aPKC signal-coupling. Various biochemical and functional assays will be used to define the function of src in regulation of aPKC signaling. Overall, a comprehensive set of experiments using enzyme activity assays, subcellular fractionation, coimmunoprecipitation and site-directed mutagenesis will be employed. The outcome of this work will continue to alter the conceptual framework of neurotrophic signal coupling and the role that aPKC plays in this process. These findings will contribute to further understanding of the mechanism whereby aPKC is regulated and may provide new therapeutic targets for neurodegenerative disorders.

描述（根据申请人的摘要改编）： 非典型PKC同工型（IOTA/ZETA）已显示在 调节各种神经元过程，包括分化，生存 和长期增强。在PC-12单元格中，PKC及其第二个 Messenger激活剂P13 p13聚磷酸肌醇都需要两者 分化和生存反应。我们最近表明APKC是 酪氨酸响应神经生长因子（NGF）而磷酸化。 zip/p62和 PAR4是结合蛋白，调节定位和激活 APKC。初步研究记录了NGF受体调节的磷酸酪氨酸 SRC与SPKC的依赖相互作用。我们假设酪氨酸 SRC对非典型PKC的磷酸化调节活动，以及它 与其蛋白质调节剂PAR4和拉链相互作用的能力。因此，一个 具体目的是研究APKC-iota受到调节的机制 酪氨酸pHSophophylation以包括NGF受体成分调节，P75 和TRKA，以及第二使者。第二个目的是解开 APKC的机制受SRC激酶调节以包括对APKC的调节 定位，信号复合形成以及与蛋白质调节剂的相互作用， 以及检查调节NGF/APKC的特定酪氨酸残基 信号耦合。各种生化和功能测定将用于 定义SRC在APKC信号调节中的功能。总体而言， 使用酶活性测定，亚细胞的全面实验集 分馏，共免疫沉淀和定向诱变将是 雇用。这项工作的结果将继续改变概念 神经营养信号耦合的框架和APKC在此中扮演的作用 过程。这些发现将有助于进一步理解 通过调节APKC的机制，可能为新的治疗靶标提供 神经退行性疾病。