Trans-dimerization of JAM-A regulates Rap2 and is mediated by a domain that is distinct from the cis-dimerization interface

© 2014 Monteiro et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0)..

Junctional adhesion molecule-A (JAM-A) is a tight junction-associated signaling protein that regulates epithelial cell proliferation, migration, and barrier function. JAM-A dimerization on a common cell surface (in cis) has been shown to regulate cell migration, and evidence suggests that JAM-A may form homodimers between cells (in trans). Indeed, transfection experiments revealed accumulation of JAM-A at sites between transfected cells, which was lost in cells expressing cis- or predicted trans-dimerization null mutants. Of importance, microspheres coated with JAM-A containing alanine substitutions to residues 43NNP45 (NNP-JAM-A) within the predicted trans-dimerization site did not aggregate. In contrast, beads coated with cis-null JAM-A demonstrated enhanced clustering similar to that observed with wild-type (WT) JAM-A. In addition, atomic force microscopy revealed decreased association forces in NNP-JAM-A compared with WT and cis-null JAM-A. Assessment of effects of JAM-A dimerization on cell signaling revealed that expression of trans- but not cis-null JAM-A mutants decreased Rap2 activity. Furthermore, confluent cells, which enable trans-dimerization, had enhanced Rap2 activity. Taken together, these results suggest that trans-dimerization of JAM-A occurs at a unique site and with different affinity compared with dimerization in cis. Trans-dimerization of JAM-A may thus act as a barrier-inducing molecular switch that is activated when cells become confluent.

Medienart:

E-Artikel

Erscheinungsjahr:

2014

Erschienen:

2014

Enthalten in:

Zur Gesamtaufnahme - volume:25

Enthalten in:

Molecular biology of the cell - 25(2014), 10 vom: 26. Mai, Seite 1574-85

Sprache:

Englisch

Beteiligte Personen:

Monteiro, Ana C [VerfasserIn]
Luissint, Anny-Claude [VerfasserIn]
Sumagin, Ronen [VerfasserIn]
Lai, Caroline [VerfasserIn]
Vielmuth, Franziska [VerfasserIn]
Wolf, Mattie F [VerfasserIn]
Laur, Oskar [VerfasserIn]
Reiss, Kerstin [VerfasserIn]
Spindler, Volker [VerfasserIn]
Stehle, Thilo [VerfasserIn]
Dermody, Terence S [VerfasserIn]
Nusrat, Asma [VerfasserIn]
Parkos, Charles A [VerfasserIn]

Links:

Volltext

Themen:

Cell Adhesion Molecules
EC 3.6.1.-
EC 3.6.5.2
F11R protein, human
Journal Article
RAP2A protein, human
RNA, Small Interfering
Rap GTP-Binding Proteins
Receptors, Cell Surface
Research Support, N.I.H., Extramural

Anmerkungen:

Date Completed 13.01.2015

Date Revised 21.10.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1091/mbc.E14-01-0018

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM236790471