The orphan receptor GPR55 is a novel cannabinoid receptor.

Abstract in brief

• GPR55 is identified as a new type of cannabinoid receptor that can bind various cannabinoids, including compounds like CP55940, anandamide, and virodhamine, activating specific G-proteins such as Galpha13.
• Unlike the well-known CB1 and CB2 receptors, GPR55 interacts with different ligands, including some like cannabidiol that do not activate CB1 or CB2, indicating it might have unique physiological roles.
• The receptor’s activation leads to the stimulation of downstream signaling pathways involving proteins like rhoA, cdc42, and rac1, which are important for various cellular functions, highlighting its potential importance in the endocannabinoid system.]