Adhesion G protein-coupled receptor B3 (ADGRB3)

Adhesion G protein-coupled receptor B3 (ADGRB3), also known as BAI3, is a member of the adhesion GPCR family with a large extracellular domain responsible for cell–cell adhesion and signaling[1][3][4][5]. Highly expressed in the brain, ADGRB3 is crucial for synaptic development, dendritic morphogenesis, and the elimination of redundant synapses, impacting circuit refinement essential for motor learning and cognition[1][2]. It interacts with secreted C1q-like proteins to regulate synaptic density, and its disruption is implicated in neurodevelopmental disorders[1][2]. Beyond the nervous system, ADGRB3 mediates myoblast fusion in muscle and modulates metabolic and angiogenic pathways[1][3][5]. Aberrant ADGRB3 expression or genomic alteration is linked to certain malignancies (lung, breast, ovarian, gastric, prostate) and vascular or metabolic diseases including insulin regulation and venous thromboembolism[1][3][5]. No drugs currently target ADGRB3 directly, but its roles in diverse physiological and pathological processes are under investigation as potential therapeutic opportunities.

Other names

BAI3Brain-specific angiogenesis inhibitor 3KIAA0550dJ91B17.1BAI-3

Not established—ADGRB3 is considered an orphan receptor (no approved drugs directly targeting it); Signal regulation via tethered agonist after autoproteolytic cleavage within the GAIN domain; Binds secreted C1q-like proteins; modulates synaptic density and insulin secretion through downstream signaling.