神经生物学前沿学术报告 

报告题目:  Neurexins Cluster Ca2+ Channels within presynaptic Active Zone

报告人:    Fujun Luo, Ph.D

Stanford University

时间：    2019年10月9日（周三），下午：15:00-16:00

地点：    西区生物楼429会议室

主办单位：中国科学院脑功能与脑疾病重点实验室

中国科学技术大学生命科学学院

合肥微尺度物质科学国家研究中心集成影像中心

报告简介：

To achieve ultrafast neurotransmission, neurons assemble synapses with highly organized presynaptic and postsynaptic nanomachines that are aligned by synaptic adhesion molecules. How functional assembly of presynaptic active zone is controlled via trans-synaptic interactions remains unknown. Here, we conditionally deleted all neurexins from presynaptic neurons of the calyx of Held, a model synapse that allows precise biophysical analyses of synaptic properties. The pan-neurexin deletion had no effect on synapse developmentor the basic release machinery, but dramatically impaired fast neurotransmitter release. The overall properties of presynaptic Ca2+ channels appeared normal, as reflected by the similar characteristics of Ca2+ currents recorded at the nerve terminals. However, the tight coupling of Ca2+-influx to exocytosis was significantly impaired in neurexin-deficient synapses. Furthermore, such decoupling was supplemented by a large reduction in the function of BK channels, the activation of which depends on their tight association with presynaptic Ca2+ channels. Together, these results suggest that neurexins play a major function at the calyx synapse in tightly organizing presynaptic Ca2+channels at release sites.