JAM3 Human

Junctional Adhesion Molecule 3 (JAM3) is a member of the immunoglobulin superfamily and plays a crucial role in cell-cell adhesion. It is primarily localized at the tight junctions of epithelial and endothelial cells. JAM3 is involved in various physiological processes, including maintaining endothelial barrier integrity, regulating leukocyte migration, and contributing to angiogenesis.

JAM3 was identified as the third member of the junctional adhesion molecule family. It shares 36% and 32% identity with JAM2 and JAM1, respectively . The gene encoding JAM3 is located on chromosome 11q25 and is expressed in various tissues, with higher levels observed in the kidney, brain, and placenta .

JAM3 is a transmembrane protein that interacts with other members of the JAM family and various scaffolding proteins, such as ZO-1, claudin, and afadin . These interactions are essential for the formation and maintenance of tight junctions and adherens junctions. JAM3 also binds to JAM2, forming a heterotypic interaction that plays a role in leukocyte adhesion and migration .

JAM3 is involved in several physiological processes, including:

• Endothelial Barrier Maintenance: JAM3 helps maintain the integrity of the endothelial barrier, preventing the uncontrolled passage of solutes and cells .
• Leukocyte Migration: JAM3 regulates the migration of leukocytes across the endothelium during inflammation .
• Angiogenesis: JAM3 contributes to the formation of new blood vessels, a process critical for tissue repair and growth .

Mutations in the JAM3 gene have been associated with various pathological conditions, including brain hemorrhages, subependymal calcification, and congenital cataracts .

Recombinant JAM3 is used in research to study its role in cell adhesion, migration, and signaling pathways. It is also employed in developing therapeutic strategies for diseases involving endothelial dysfunction and abnormal leukocyte migration.