title: Involvement of nectin in the localization of junctional adhesion molecule at tight junctions.
abstract: Junctional adhesion molecule (JAM) is a Ca2+-independent immunoglobulin-like cell-cell adhesion molecule which localizes at tight junctions (TJs). Claudin is a key cell-cell adhesion molecule that forms TJ strands at TJs. JAM is associated with claudin through their cytoplasmic tail-binding protein, ZO-1. JAM is furthermore associated with Par-3, a cell polarity protein which forms a ternary complex with Par-6 and atypical protein kinase C. Nectin is another Ca2+-independent immunoglobulin-like cell-cell adhesion molecule which localizes at adherens junctions (AJs). Nectin is associated with E-cadherin through their respective cytoplasmic tail-binding proteins, afadin and catenins, and involved in the formation of AJs cooperatively with E-cadherin. We show here that nectin is furthermore involved in the localization of JAM at TJs. During the formation of the junctional complex consisting of AJs and TJs in Madin-Darby canine kidney (MDCK) cells, JAM was recruited to the nectin-based cell-cell adhesion sites. This recruitment of JAM was inhibited by nectin inhibitors, which inhibited the trans-interaction of nectin. Microbeads coated with the extracellular fragment of nectin, that interacted with cellular nectin, also recruited JAM to the bead-MDCK cell contact sites. Furthermore, when cadherin-deficient L fibroblasts stably expressing both exogenous JAM and nectin (nectin-JAM-L cells) were co-cultured with L fibroblasts expressing only nectin (nectin-L cells), JAM was concentrated at the cell-cell adhesion sites between nectin-JAM-L and nectin-L cells without the trans-interaction of JAM. Analyses of the localization and immunoprecipitation of JAM revealed that it was associated with nectin through afadin and ZO-1. These results suggest that nectin has a role in the localization of JAM at TJs in the process of the formation of the junctional complex in epithelial cells.
authors.affiliation: Department of Molecular Biology and Biochemistry, Osaka University Graduate School of Medicine/Faculty of Medicine, Suita 565-0871, Japan.
authors.forename: Atsunori
authors.initials: A
authors.lastname: Fukuhara
authors.forename: Kenji
authors.initials: K
authors.lastname: Irie
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakanishi
authors.forename: Kyoji
authors.initials: K
authors.lastname: Takekuni
authors.forename: Tomomi
authors.initials: T
authors.lastname: Kawakatsu
authors.forename: Wataru
authors.initials: W
authors.lastname: Ikeda
authors.forename: Akio
authors.initials: A
authors.lastname: Yamada
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Katata
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Honda
authors.forename: Tatsuhiro
authors.initials: T
authors.lastname: Sato
authors.forename: Kazuya
authors.initials: K
authors.lastname: Shimizu
authors.forename: Harunobu
authors.initials: H
authors.lastname: Ozaki
authors.forename: Hisanori
authors.initials: H
authors.lastname: Horiuchi
authors.forename: Toru
authors.initials: T
authors.lastname: Kita
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Takai
mesh_terms: D000818:Animals; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D015815:Cell Adhesion Molecules / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D018920:Coculture Techniques; D004285:Dogs; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects; D007365:Intercellular Junctions / Q000378:metabolism*; D062726:Junctional Adhesion Molecules; D007668:Kidney / Q000166:cytology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism; D000075983:Nectins; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D062826:Zonula Occludens-1 Protein
chemical_list: D015820:Cadherins; D015815:Cell Adhesion Molecules; D062726:Junctional Adhesion Molecules; D008565:Membrane Proteins; D008840:Microfilament Proteins; D000075983:Nectins; D010750:Phosphoproteins; D011994:Recombinant Proteins; D062826:Zonula Occludens-1 Protein; C108835:afadin; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium