Immunoglobulin superfamily member 21 (IGSF21)

Immunoglobulin superfamily member 21 (IGSF21) is a GPI-anchored membrane protein containing two (or three, depending on isoform) immunoglobulin-like domains and is part of the immunoglobulin superfamily. It is specifically expressed in the brain on the postsynaptic membrane and acts as a synaptic adhesion molecule that interacts with presynaptic neurexin2α, facilitating the selective differentiation and organization of inhibitory (GABAergic) synapses, especially in the hippocampus and cortex. Knockout mouse studies show that IGSF21 is essential for proper inhibitory synaptic transmission and that its absence leads to deficits in CNS inhibitory networks and sensorimotor gating. IGSF21 is not currently associated with any therapeutic drugs or direct biomarker applications, but its biological role makes it relevant to the fundamental understanding of inhibitory synapse regulation in the central nervous system.

Other names

Immunoglobulin superfamily member 21IGSF21IgSF21MGC15730RP11-121A23.1

Not applicable; there are no drugs or small molecules reported to modulate IGSF21, so no drug mechanisms of action are described.