An Arf6- and caveolae-dependent pathway links hemidesmosome remodeling and mechanoresponse.

Fiche publication


Date publication

février 2018

Journal

Molecular biology of the cell

Auteurs

Membres identifiés du Cancéropôle Est :
Dr GOETZ Jacky, Pr RIVELINE Daniel, Dr OSMANI Naël


Tous les auteurs :
Osmani N, Pontabry J, Comelles J, Fekonja N, Goetz JG, Riveline D, Georges-Labouesse E, Labouesse M

Résumé

Hemidesmosomes (HDs) are epithelial-specific cell-matrix adhesions that stably anchor the intracellular keratin network to the extracellular matrix. Although their main role is to protect the epithelial sheet from external mechanical strain, how HDs respond to mechanical stress remains poorly understood. Here we identify a pathway essential for HD remodeling and outline its role with respect to α6β4 integrin recycling. We find that α6β4 integrin chains localize to the plasma membrane, caveolae, and ADP-ribosylation factor-6+ (Arf6+) endocytic compartments. Based on fluorescence recovery after photobleaching and endocytosis assays, integrin recycling between both sites requires the small GTPase Arf6 but neither caveolin1 (Cav1) nor Cavin1. Strikingly, when keratinocytes are stretched or hypo-osmotically shocked, α6β4 integrin accumulates at cell edges, whereas Cav1 disappears from it. This process, which is isotropic relative to the orientation of stretch, depends on Arf6, Cav1, and Cavin1. We propose that mechanically induced HD growth involves the isotropic flattening of caveolae (known for their mechanical buffering role) associated with integrin diffusion and turnover.

Mots clés

ADP-Ribosylation Factors, metabolism, Caveolin 1, metabolism, Cell Line, Cell Membrane, metabolism, Hemidesmosomes, metabolism, Humans, Integrin beta4, metabolism, Keratinocytes, metabolism, Microscopy, Electron, Transmission, Microscopy, Immunoelectron

Référence

Mol. Biol. Cell. 2018 Feb 15;29(4):435-451