Q9Y624 

JAMA(F11R, JAM-1, CD321) is a cell-surface adhesion molecule belonging to the Ig superfamily of receptors. CD321 is a 32-41 kD glycoprotein, possessing two extracellular Ig-like domains, a transmembrane region, and a short cytosolic tail. The protein assembles at the membrane as a homodimer, and can associate laterally with other membrane proteins including integrins. CD321 is expressed on a variety of cell types, including leukocytes, platelets, erythrocytes, stem cells, epithelial and endothelial cells, and plays a role in mediating cell-cell contact. CD321 can be found in close proximity to several components of epithelial tight junctions, including ZO-1 and occludin. CD321 is involved in the maintenance of epithelial and endothelial barriers, hematopoiesis, angiogenesis, and tumor proliferation, invasion, and metastasis.