NMDA受体GluN2B亚基酪氨酸磷酸化调控新机制及其在脑缺血损伤中的作用

NMDA受体是多亚基谷氨酸门控离子通道，因其GluN2亚基的不同而形成功能迥异的受体亚型，并在许多生理和病理过程中导致不同的后果。因而，揭示NMDA受体亚基选择性调控机制及其在特定生理和病理过程的作用具有重要意义。以往研究提示脑缺血损伤与突触外NMDA受体及GluN2B亚基更为关联，也与GluN2B的1472酪氨酸磷酸化上调有关，然而，相关机制有待进一步阐明。申请人最近发现GluN2B胞内C端的1070和1472酪氨酸磷酸化位点存在协同调控的新机制，并成功制作了GluN2B-Y1070F突变小鼠。本项目拟应用GluN2B-Y1070F突变小鼠，并组合使用生化、药理学、电生理及行为学等方法，从in vivo水平深入阐明GluN2B亚基Y1070协同调控Y1472磷酸化机制，验证其是否为多信号途径调控Y1472磷酸化的共同通路，并探索其在脑缺血损伤中的作用、机制及选择性干预。

N-methyl-D-aspartate (NMDA) receptor is a glutamate gated ion channel formed by multiple subunits, and different NMDA receptor subtypes determined by GluN2 subunits have the differential functions in all kinds of physiological and pathological conditions. Herein, it is significant to uncover the differential regulation mechanism of NMDA receptor subunit and its role in specific condition. Accumulating evidence suggested GluN2B contained NMDA receptor at extra-synaptic sites is mainly involved in brain ischemia injury, and tyrosine phosphorylation of GluN2B at 1472 site is important for this process, however, the mechanism is largely unknown. One of the applicant recent studies uncovered a novel mechanism which 1070 site regulated the phosphorylation of 1472 tyrosine site, and we have constructed the GluN2B-Y1070F knockin mice. By combining pharmacology, biochemistry, electrophysiology and behavior test techniques, we aim to determine whether 1070 site regulated phosphorylation of 1472 site is the common pathway of multiple signaling pathways induced phosphorylation of 1472 site, elaborate the role and underly the mechanism of 1070 tyrosine site in ischemia injury in vivo, and try to provide a novel therapeutic target for stroke in future.