Article

Neurexin-neuroligin signaling in synapse development.

Brain Research Centre, University of British Columbia, 2211 Wesbrook Mall, Vancouver V6T 2B5, Canada.
Current Opinion in Neurobiology (Impact Factor: 6.77). 03/2007; 17(1):43-52. DOI: 10.1016/j.conb.2007.01.011
Source: PubMed

ABSTRACT Neurexins and neuroligins are emerging as central organizing molecules for excitatory glutamatergic and inhibitory GABAergic synapses in mammalian brain. They function as cell adhesion molecules, bridging the synaptic cleft. Remarkably, each partner can trigger formation of a hemisynapse: neuroligins trigger presynaptic differentiation and neurexins trigger postsynaptic differentiation. Recent protein interaction assays and cell culture studies indicate a selectivity of function conferred by alternative splicing in both partners. An insert at site 4 of beta-neurexins selectively promotes GABAergic synaptic function, whereas an insert at site B of neuroligin 1 selectively promotes glutamatergic synaptic function. Initial knockdown and knockout studies indicate that neurexins and neuroligins have an essential role in synaptic transmission, particularly at GABAergic synapses, but further studies are needed to assess the in vivo functions of these complex protein families.

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