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bioRxiv · 10.1101/809343

Nectins rather than E-cadherin anchor the actin belts at cell-cell junctions of epithelia

Mangeol, P.·Massey-Harroche, D.·Le Bivic, A.·Lenne, P.-F.
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Abstract

Cell-cell junctions support the mechanical integrity of epithelia by enabling adhesion and tension transmission between neighboring cells. The prevailing mechanistic dogma is that E-cadherin supports and transmits mechanical tension between cells through actin belts in a region named the zonula adherens. Using super-resolution microscopy on human intestinal biopsies and Caco-2 cells, we show that the zonula adherens consists of E-cadherin and nectin belts that are separated by about 150 nm along the apico-basal direction, the nectin belt being in the immediate vicinity of the actin belt. The segregation of nectins and E-cadherin increases as the tissue matures. Our data redefine the structure of the zonula adherens and show that nectins, rather than E-cadherin, are the major connectors of actin belts in epithelia.

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Mangeol, P., Massey-Harroche, D., Le Bivic, A., Lenne, P.-F.. 2019-10-17. Nectins rather than E-cadherin anchor the actin belts at cell-cell junctions of epithelia. https://doi.org/10.1101/809343

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