JAM-A is a member of the immunoglobulin superfamily found on the surface of mouse platelets and at intercellular junctions of endothelial cells and epithelial cells. JAM-A belongs together with JAM-B (VE-JAM or JAM-3) and JAM-C (JAM-2) to a family of adhesion proteins with a V-C2 immunoglobulin domain organization. JAM plays an important role in tight junctions where it is involved in cell-to-cell adhesion through homophilic interaction. It codistributes with other tight junction components as ZO-1, 7H6 antigen, cingulin and occludin. In human JAM-A plays a role in platelet aggregation, secretion, adhesion and spreading.Synonyms: F11R, JAM-A, JCAM, Junctional adhesion molecule 1, Junctional adhesion molecule A, PAM1, Platelet F11 receptor, Platelet adhesion molecule 1