Global phosphoproteomic analysis in nerve terminal during exocytosis reveals 252 uniquely regulated phosphosites, highlighting complex regulation of active zone proteins at multiple sites and the role of specific kinases/phosphatases.
Clarinet, a novel C. elegans active zone protein with homology to vertebrate Piccolo and Rim, uses its different isoforms for diverse functions, including synaptic vesicle clustering, vesicle release and synaptogenesis.
High affinity interactions with transport adaptors are important to shield the interaction surfaces of cytomatrix components to block fatal premature oligomerization of active zone proteins during axonal transport.
A novel region in the CaV2.1 α1 subunit regulates coupling of synaptic vesicles to CaV2.1 calcium channels, synaptic vesicle release and docking, and the size of the fast and total releasable pools of synaptic vesicles.
Active zone release probability is correlated with calcium channel density and calcium influx at single release sites, with release strength increasing in an activity-dependent manner during synapse maturation.