A great variety of cell adhesion molecules links presynaptic and postsynaptic membranes across the synaptic cleft. Many of them play a role at various stages of synaptic differentiation, synaptic transmission, and synapse maintenance.
In one example, neurexins expressed by the axons bind to their partners (neuroligins) present in the postsynaptic membrane. A research study that looked at the role of neurexins in development found that absence of neurexins did not affect formation of synapses. Yet, both spontaneous (miniature potentials) and evoked synaptic activity was greatly diminished at both GABAergic and glutamatergic synapses.
What is the role of neurexins in synaptogenesis?