The Molecular Mechanisms Underlying Synaptic Transmission: A View of the Presynaptic Terminal

Synaptic transmission relies on spatially and temporally coordinated multistep processes that allow neuronal communication; activity-dependent changes in synaptic transmission underlie synaptic plasticity. These processes are coordinated by a large number of specific proteins whose dynamic interactions, expression, and regulation define the efficacy of transmission and the mode of synaptic plasticity. In this chapter, we discuss the molecular mechanisms of some of the basic processes associated with neurotransmission in the presynaptic terminal—vesicle docking, priming, and fusion—elaborate on the contribution of specific proteins to different modes of vesicle recycling, and discuss their nanoscale distribution in the synapses. We also describe the involvement of these proteins in synaptic plasticity and animal behavior, the expression ratios between specific proteins and the possible contribution of these ratios to various modes and kinetics of neurotransmitter release.