Junctional adhesion protein that mediates heterotypic cell-cell interactions with its cognate receptor JAM2 to regulate different cellular processes (, ). Plays a role in homing and mobilization of hematopoietic stem and progenitor cells within the bone marrow. At the surface of bone marrow stromal cells, it contributes to the retention of the hematopoietic stem and progenitor cells expressing JAM3 (, ). Plays a central role in leukocytes extravasation by facilitating transmigration through the endothelium (By similarity). Plays a role in spermatogenesis where JAM2 and JAM3, which are respectively expressed by Sertoli and germ cells, mediate an interaction between both cell types and play an essential role in the anchorage of germ cells onto Sertoli cells and the assembly of cell polarity complexes during spermatid differentiation (By similarity). Also functions as a counter-receptor for ITGAM, mediating leukocyte-platelet interactions and is involved in the regulation of transepithelial migration of polymorphonuclear neutrophils (PMN) (, ). Plays a role in angiogenesis . Plays a role in the regulation of cell migration (Probable). During myogenesis, it is involved in myocyte fusion (By similarity).
Promotes chemotaxis of vascular endothelial cells and stimulates angiogenesis.
Subcellular locations: Cell membrane, Cell junction, Cell junction, Desmosome, Cell junction, Tight junction
Detected in the acrosome region in developing spermatids (By similarity). In epithelial cells, it is expressed at desmosomes but not at tight junctions . Localizes at the cell surface of endothelial cells; treatment of endothelial cells with vascular endothelial growth factor stimulates recruitment of JAM3 to cell-cell contacts .
Subcellular locations: Secreted
Detected on round and elongated spermatids (at protein level) . Highest expression in placenta, brain and kidney. Significant expression is detected on platelets. Expressed in intestinal mucosa cells. Expressed in the vascular endothelium. Found in serum (at protein level). Also detected in the synovial fluid of patients with rheumatoid arthritis, psoriatic arthritis or ostearthritis (at protein level).