Neuroligins (NLGNs) are a family of postsynaptic cell adhesion molecules that play an important role in synaptic development and function¹. Four genes encode for the different members of the neuroligin family in mammals: NLGN 1-4, which are differentially enriched in postsynaptic specializations of synapses². Neuroligin 2 (NLGN2) is expressed in neurons in the brain and also in pancreatic β cells where it facilitates insulin secretion³.

Synaptic maturation is promoted by the binding of Neuroligin 2 with presynaptic Neurexins, and these interactions are restricted to particular combinations of isoforms of the binding partners³. NLGN2 plays a role in synapse function and synaptic signal transmission, especially via γ-aminobutyric acid receptors (GABA(A) receptors). NLGN2 modulates signaling by inhibitory synapses, and thereby plays a role in controlling the ratio of signaling by excitatory and inhibitory synapses and information processing⁴.

Recent studied identified a loss-of-function mutation of NLGN2 in schizophrenia patients, suggesting an indispensable role of NLGN2 in regulating GABAergic functions⁵.