ARHGAP10 is necessary for alpha-catenin recruitment at adherens junctions and for Listeria invasion.
E-cadherin mediates the formation of adherens junctions between epithelial cells. It serves as a receptor for Listeria monocytogenes, a bacterial pathogen that enters epithelial cells. The L. monocytogenes surface protein, InlA, interacts with the extracellular domain of E-cadherin. In adherens junctions, this ectodomain is involved in homophilic interactions whereas the cytoplasmic domain binds beta-catenin, which then recruits alpha-catenin. alpha-catenin binds to actin directly, or indirectly, thus linking E-cadherin to the actin cytoskeleton. Entry of L. monocytogenes into cells and adherens junction formation are dynamic events that involve actin and membrane rearrangements. To understand these processes better, we searched for new ligands of alpha-catenin. Using a two-hybrid screen, we identified a new partner of alpha-catenin: ARHGAP10. This protein colocalized with alpha-catenin at cell-cell junctions and was recruited at L. monocytogenes entry sites. In ARHGAP10-knockdown cells, L. monocytogenes entry and alpha-catenin recruitment at cell-cell contacts were impaired. The GAP domain of ARHGAP10 has GAP activity for RhoA and Cdc42. Its overexpression disrupted actin cables, enhanced alpha-catenin and cortical actin levels at cell-cell junctions and inhibited L. monocytogenes entry. Altogether, our results show that ARHGAP10 is a new component of cell-cell junctions that controls alpha-catenin recruitment and has a key role during L. monocytogenes uptake.
Sousa
Sandra
S
Unité des Interactions Bactéries-Cellules Institut Pasteur, INSERM U604, INRA USC2020, 28 Rue du Dr Roux, 75724 Paris Cedex 15, France.
Cabanes
Didier
D
Archambaud
Cristel
C
Colland
Frédéric
F
Lemichez
Emmanuel
E
Popoff
Michel
M
Boisson-Dupuis
Stéphanie
S
Gouin
Edith
E
Lecuit
Marc
M
Legrain
Pierre
P
Cossart
Pascale
P
D000199:Actins / Q000502:physiology; D022005:Adherens Junctions / Q000502:physiology*; D000818:Animals; D001426:Bacterial Proteins / Q000502:physiology; D018938:Caco-2 Cells; D002448:Cell Adhesion / Q000502:physiology; D002460:Cell Line; D002462:Cell Membrane / Q000502:physiology; D020690:GTPase-Activating Proteins / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D007365:Intercellular Junctions / Q000502:physiology*; D008024:Ligands; D008089:Listeria monocytogenes / Q000502:physiology*; D034622:RNA Interference / Q000502:physiology; D020798:Two-Hybrid System Techniques; D051178:alpha Catenin / Q000502:physiology*; D020742:rhoA GTP-Binding Protein
C486050:ARHGAP10 protein, human; D000199:Actins; D001426:Bacterial Proteins; D020690:GTPase-Activating Proteins; D008024:Ligands; D051178:alpha Catenin; C069761:internalin protein, Bacteria; D020742:rhoA GTP-Binding Protein