Conserved arginine residues in synaptotagmin 1 regulate fusion pore expansion through membrane contact

Abstract

Synaptotagmin 1 (Syt1) is the calcium sensor for fast synchronous neurotransmitter release but the mechanism by which it functions is still under debate. Here, the authors combine EPR measurements and functional studies and observe that different faces of the Syt1 C2B domain play different roles in regulating neurotransmitter release and they show that the expansion of the fusion pore is mediated by membrane contact of the C2B arginine apex.