Involved in the targeting and/or fusion of transport vesicles to their target membrane. Acts in neuronal exocytosis of synaptic transmission. Likely to have a role in cholinergic transmisson. Required for viability, coordinated movement and M3 pharynx motor neuron function (By similarity). Part of the SNARE core complex containing CBG09569/SNAP25, snb-1/VAMP2 and CBG03570/STX1A. This complex binds to cpx-1/CPLX1 (By similarity). Belongs to the synaptobrevin family.