Regulation of synapses by cdk5-dependent phosphorylation

通过 cdk5 依赖性磷酸化调节突触

• 批准号: 6920046
• 负责人: MARIA A MORABITO
• 金额: $ 28.9万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-15 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6920046
• 关键词: AMPA receptors; NMDA receptors; SDS polyacrylamide gel electrophoresis; cyclin dependent kinase; electrospray ionization mass spectrometry; enzyme activity; fatty acylation; genetically modified animals; green fluorescent proteins; intracellular transport; laboratory mouse; laboratory rat; matrix assisted laser desorption ionization; nerve /myelin protein; neurophysiology; neuroregulation; palmitates; phosphorylation; posttranslational modifications; protein localization; protein transport; receptor binding; receptor expression; synapses; tissue /cell culture

DESCRIPTION (provided by applicant): Synapses are highly specialized dynamic structures, site of neurotransmitter release and postsynaptic responses. Synaptic dysfunction has been implicated in a number of developmental, psychiatric, and neurodegenerative disorders. Cdk5 is a kinase essential for brain development and implicated in synaptic function and neurodegenerative disorders. Our studies indicate that cdk5 phosphorylates the postsynaptic protein PSD-95 in vivo. PSD-95 is a scaffolding protein implicated in the stabilization and signaling of glutamate receptor at synapses. Since cdk5-dependent phosphorylation of PSD-95 decreases PSD-95 association with membranes and clustering of PSD-95, we propose to test the hypothesis that phosphorylation negatively affects the intracellular trafficking of PSD-95 and its ability to stabilize glutamate receptors at synapses. Furthermore, we will test the possibility that cdk5 activity and cdk5-dependent phosphorylation of PSD-95 are regulated by glutamate receptors activity. The specific aims of this proposal are: 1) To characterize the biochemical properties of phosphorylated PSD-95; 2) To elucidate the regulation of cdk5-dependent phosphorylation of PSD-95; 3) To assess the impact of phosphorylated PSD-95 on trafficking of PSD-95 and glutamate receptors. This novel research proposal will use established biochemical, immmunocytochemical, and imaging methods to address the impact of the cdk5-dependent phosphorylation on synaptic organization and function. These studies will provide new insight into the molecular organization and regulation of synapses, and the molecular mechanisms responsible for the formation of brain circuitry, learning, and memory. The long-term goal of this project is to further our understanding of the function of cdk5 at synapses and to identify molecular mechanisms relevant to synapse function. These results will be relevant to neurodegenerative and psychiatric disorders associated with synaptic dysfunction, such as Alzheimer's, Huntington's, and schizophrenia.

描述（由申请人提供）：突触是高度专业化的动态结构，是神经递质释放和突触后反应的部位。突触功能障碍与许多发育、精神和神经退行性疾病有关。 Cdk5 是一种对大脑发育至关重要的激酶，与突触功能和神经退行性疾病有关。我们的研究表明 cdk5 在体内磷酸化突触后蛋白 PSD-95。 PSD-95 是一种支架蛋白，参与突触谷氨酸受体的稳定和信号传导。由于 PSD-95 的 cdk5 依赖性磷酸化会降低 PSD-95 与膜的关联以及 PSD-95 的聚集，因此我们建议检验磷酸化对 PSD-95 的细胞内运输及其稳定突触谷氨酸受体的能力产生负面影响的假设。此外，我们将测试 cdk5 活性和 PSD-95 的 cdk5 依赖性磷酸化受谷氨酸受体活性调节的可能性。该提案的具体目标是： 1) 表征磷酸化 PSD-95 的生化特性； 2) 阐明PSD-95的cdk5依赖性磷酸化的调控； 3) 评估磷酸化 PSD-95 对 PSD-95 和谷氨酸受体运输的影响。这项新颖的研究计划将使用已建立的生化、免疫细胞化学和成像方法来解决 cdk5 依赖性磷酸化对突触组织和功能的影响。这些研究将为突触的分子组织和调节，以及负责大脑回路、学习和记忆形成的分子机制提供新的见解。该项目的长期目标是进一步了解 cdk5 在突触中的功能，并确定与突触功能相关的分子机制。这些结果将与与突触功能障碍相关的神经退行性疾病和精神疾病相关，例如阿尔茨海默病、亨廷顿舞蹈症和精神分裂症。