title: JAM-2, a novel immunoglobulin superfamily molecule, expressed by endothelial and lymphatic cells.
abstract: Cell-cell contacts are essential for morphogenesis and tissue function and play a vital role in mediating endothelial cohesion within the vascular system during vessel growth and organization. We identified a novel junctional adhesion molecule, named JAM-2, by a selective RNA display method, which allowed identification of transcripts encoding immunoglobulin superfamily molecules regulated during coculture of endothelial cells with tumor cells. The JAM-2 transcript is highly expressed during embryogenesis and is detected in lymph node and Peyer's patches RNA of adult mice. Accordingly, antibodies specific for JAM-2 stain high endothelial venules and lymphatic vessels in lymphoid organs, and vascular structures in the kidney. Using real time video microscopy, we show that JAM-2 is localized within minutes to the newly formed cell-cell contact. The role of the protein in the sealing of cell-cell contact is further suggested by the reduced paracellular permeability of cell monolayer transfected with JAM-2 cDNA, and by the localization of JAM-2 to tight junctional complexes of polarized cells. Taken together, our results suggest that JAM-2 is a novel vascular molecule, which participates in interendothelial junctional complexes.
authors.affiliation: Department of Pathology, Centre Medical Universitaire, 1 rue Michel-Servet, CH-1211 Geneva, Switzerland. michel.aurrand-lions@medecine.unige.ch
authors.forename: M
authors.initials: M
authors.lastname: Aurrand-Lions
authors.forename: L
authors.initials: L
authors.lastname: Duncan
authors.forename: C
authors.initials: C
authors.lastname: Ballestrem
authors.forename: B A
authors.initials: BA
authors.lastname: Imhof
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000302:isolation & purification*; D002451:Cell Compartmentation; D016764:Cell Polarity; D004729:Endothelium, Lymphatic / Q000737:chemistry* / Q000648:ultrastructure; D004730:Endothelium, Vascular / Q000737:chemistry* / Q000648:ultrastructure; D007136:Immunoglobulins / Q000235:genetics / Q000302:isolation & purification*; D007668:Kidney / Q000098:blood supply; D008565:Membrane Proteins / Q000235:genetics / Q000302:isolation & purification*; D051379:Mice; D008969:Molecular Sequence Data; D011956:Receptors, Cell Surface; D017386:Sequence Homology, Amino Acid; D019108:Tight Junctions / Q000737:chemistry* / Q000648:ultrastructure; D014018:Tissue Distribution; D062765:Junctional Adhesion Molecule B
chemical_list: D015815:Cell Adhesion Molecules; D007136:Immunoglobulins; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; C498686:F11r protein, mouse; C498781:Jam2 protein, mouse; D062765:Junctional Adhesion Molecule B; C486723:Jam3 protein, mouse