Neuroligin 4, X-Linked (NLGN4X)

NLGN4X encodes a member of the neuroligin family of neuronal cell surface proteins. Neuroligins may act as splice site-specific ligands for beta-neurexins and may be involved in the formation and remodeling of central nervous system synapses. The encoded protein interacts with discs, large (Drosophila) homolog 4 (DLG4). Mutations in this gene have been associated with autism and Asperger syndrome. Murine Nlgn4 was expressed in mouse thymus and brain, with highest expression in hippocampus, cortex, and septum, and lowest expression in brainstem and cerebellum. Nlgn4 expression increased from low levels during embryonic and early postnatal phases to reach a plateau at 3 weeks after birth, consistent with synaptic expression. Subcellular fractionation of brain homogenates showed enrichment of Nlgn4 in synaptic membrane fractions.