Nectins, which were originally identified as virus receptors, are members of the cell-cell adhesion molecule (CAM) family. They are Ca2+-independent immunoglobulin-like CAMs. The nectin family comprises four members, nectin-1, nectin-2, nectin-3 and nectin-4, which are encoded by the PVRL1, PVRL2, PVRL3 and PVRL4 genes, respectively1. In the central nervous system, these cell adhesion molecules aggregate in formations, termed puncta adherentia junctions, which are mechanical adhesive sites that connect pre- and postsynaptic membranes