JAML, a novel protein with characteristics of a junctional adhesion molecule, is induced during differentiation of myeloid leukemia cells.
Retinoic acid induces clinical remission in acute promyelocytic leukemia (APL) by triggering differentiation of leukemia promyelocytes. Here, we have characterized a gene encoding a member of the immunoglobulin superfamily, among novel retinoic acid-induced genes identified in APL cells. This protein, which was named JAML (junctional adhesion molecule-like), contains 2 extracellular immunoglobulin-like domains, a transmembrane segment, and a cytoplasmic tail. JAML mRNA is expressed in hematopoietic tissues and is prominently expressed in granulocytes. The fact that JAML protein is localized at the cell plasma membrane in the areas of cell-cell contacts, whereas it is not detected at free cell borders, suggests that JAML is engaged in homophilic interactions. Furthermore, a conserved dimerization motif among JAM members was shown to be important for JAML localization at the cell membrane. Finally, exogenous expression of JAML in myeloid leukemia cells resulted in enhanced cell adhesion to endothelial cells. Altogether, our results point to JAML as a novel member of the JAM family expressed on leukocytes with a possible role in leukocyte transmigration.
Moog-Lutz
Christel
C
Hôpital Robert Debré, Institut National de la Santé et de la Recherche Médicale, Unité U417, 48 Boulevard Serurier, 75019 Paris, France.
Cavé-Riant
Florence
F
Guibal
Florence C
FC
Breau
Marie A
MA
Di Gioia
Yolande
Y
Couraud
Pierre Olivier
PO
Cayre
Yvon E
YE
Bourdoulous
Sandrine
S
Lutz
Pierre G
PG
D001483:Base Sequence; D002448:Cell Adhesion / Q000187:drug effects; D015815:Cell Adhesion Molecules / Q000096:biosynthesis* / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D045744:Cell Line, Tumor; D004730:Endothelium, Vascular / Q000166:cytology; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D062726:Junctional Adhesion Molecules; D007951:Leukemia, Myeloid / Q000378:metabolism / Q000473:pathology*; D007962:Leukocytes / Q000166:cytology / Q000378:metabolism; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000096:biosynthesis; D017421:Sequence Analysis; D014212:Tretinoin / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D015815:Cell Adhesion Molecules; C479820:JAML protein, human; D062726:Junctional Adhesion Molecules; D012333:RNA, Messenger; D014212:Tretinoin