The specific ?-neurexin interactor calsyntenin-3 promotes excitatory and inhibitory synapse development.

ABSTRACT: Perturbations of cell surface synapse-organizing proteins, particularly ?-neurexins, contribute to neurodevelopmental and psychiatric disorders. From an unbiased screen, we identify calsyntenin-3 (alcadein-?) as a synapse-organizing protein unique in binding and recruiting ?-neurexins, but not ?-neurexins. Calsyntenin-3 is present in many pyramidal neurons throughout cortex and hippocampus but is most highly expressed in interneurons. The transmembrane form of calsyntenin-3 can trigger excitatory and inhibitory presynapse differentiation in contacting axons. However, calsyntenin-3-shed ectodomain, which represents about half the calsyntenin-3 pool in brain, suppresses the ability of multiple ?-neurexin partners including neuroligin 2 and LRRTM2 to induce presynapse differentiation. Clstn3?/? mice show reductions in excitatory and inhibitory synapse density by confocal and electron microscopy and corresponding deficits in synaptic transmission. These results identify calsyntenin-3 as an ?-neurexin-specific binding partner required for normal functional GABAergic and glutamatergic synapse development.

SUBMITTER: Pettem KL 

PROVIDER: S-EPMC3821696 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature