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bioRxiv · 10.1101/2021.09.08.459511

The function of α-Catenin mechanosensing in tissue morphogenesis

Sheppard, L.·Tepass, U.
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Abstract

-catenin couples the cadherin-catenin complex to the actin cytoskeleton. The mechanosensitive -catenin M region undergoes conformational changes upon application of force to recruit binding partners. Here, we took advantage to the tension landscape in the Drosophila embryo to define three different states of -catenin mechanosensing in support of cell adhesion. Low, medium, and high tension contacts showed -catenin M region-dependent low, medium, and high levels of Vinculin and Ajuba recruitment. In contrast, Afadin/Canoe acts in parallel to -catenin at bicellular low and medium tension junctions, but requires an interaction with -catenin for its tension-sensitive enrichment at high-tension tricellular junctions. Individual M region domains make complex contributions to cell adhesion through their impact on binding partner recruitment, and redundancies with the function of Afadin/Canoe. Our data argue that -catenin and its interaction partners are part of a cooperative and partially redundant, mechanoresponsive network that supports AJs remodelling during morphogenesis.

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Sheppard, L., Tepass, U.. 2021-09-09. The function of α-Catenin mechanosensing in tissue morphogenesis. https://doi.org/10.1101/2021.09.08.459511

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