MINTS AND SYNAPTIC VESICLE AND APP TRAFFICKING

描述(摘自申请者的摘要)：这项建议的目的是研究Mint蛋白是否是突触小泡和淀粉样前体蛋白(APP)运输的生理调节者，以神经元突触前终末的活动区为靶点。Mint1和Mint2是大脑特异的蛋白质，与Munc18-1有很高的亲和力，Munc18-1是突触囊泡胞吐所需的蛋白质。Mint的独特结构由N端的Munc18-1结合域、中间的磷酸酪氨酸结合区(PTB)和两个C端的PDZ结构域组成，这表明它可能在突触小泡排出之前的靶向和对接反应中发挥重要作用。特别有趣的是，薄荷蛋白还与APP结合，APP是淀粉样蛋白Beta4的母体蛋白，淀粉样蛋白Beta4是阿尔茨海默病发病的主要成分。由于目前尚不清楚细胞内APP交易是如何调控的，因此研究Mint蛋白的作用是一项重要的研究。因此，本研究的具体目的是：(1)研究Mint结构域在海马神经元培养中的作用；(2)通过Cre/lox重组系统的基因诱导靶向，研究Mint结构域在小鼠海马神经元培养中的功能。

DESCRIPTION (Adapted from applicant's abstract): The goal of this proposal is to investigate whether Mint proteins are physiological regulators of synaptic vesicle and amyloid precursor protein (APP) trafficking targeted to the active zone of the presynaptic terminal of neurons. Mint1 and Mint2 are brain-specific proteins and bind with high affinity to Munc18-1, a protein required for synaptic vesicle exocytosis. The unique structure of Mint composed of an N- terminal Munc18-1 binding domain, a middle phosphotyrosine-binding (PTB) domain and two C-terminal PDZ domains, thus suggests that it may play an essential role in targeting and docking reactions of synaptic vesicles prior to exocytosis. Of particular interest, Mint proteins also bind to APP, the parent protein for amyloid protein beta4, a major component in the pathogenesis of Alzheimer's disease. Since it is not known how intracellular APP trafficking is regulated, investigating the role of Mint proteins is an important study to pursue. Therefore, the specific aims are: (1) to study the role of Mint domains by transfection of Mint deletion mutants in hippocampal neuronal cultures; (2) to study the function of Mints in mice by gene-inducible targeting using the Cre/lox recombination system.