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bioRxiv · 10.1101/2023.06.05.543720

The TRIP6/LATS1 complex constitutes the tension sensor of α-catenin/vinculin at both bicellular and tricellular junctions

Abstract

Cell-cell mechanotransduction regulates tissue development and homeostasis. -catenin, the core component of adherens junctions, functions as a tension sensor and transducer by recruiting vinculin and transducing the signals to influence cell behaviors. However, little is known about the components, distributions, and dynamics of the -catenin based tension sensors at the cell junctions. Here, we uncovered the TRIP6/LATS1 complex locates at the tension sites where -catenin/vinculin is at both the bicellular junctions (BCJs) and tricellular junctions (TCJs). Vinculin/TRIP6/LATS1 are prone to form as puncta in the cytoplasm without -catenin participation. Furthermore, the tension sensing complex distributed stronger at TCJs and exhibited a discontinuously button-like pattern on BCJs. The -catenin/vinculin BiFC-based mechanosensor further proved the discontinuous distribution of the tension at BCJs, and was more motile than the TCJs. In summary, our study revealed that TRIP6 and LATS1 are novel compositions of the tension sensor, together with the core complex of -catenin/vinculin, at both the BCJs and TCJs. This work gives insights and improvements in exploring the molecular mechanism that mediates cell-cell mechanotransduction at cell junctions.

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BibTeXRIS

Xie, L., Wu, G., Liu, X., Duan, X., Zhou, K., Li, H., Ning, W.. 2023-06-06. The TRIP6/LATS1 complex constitutes the tension sensor of α-catenin/vinculin at both bicellular and tricellular junctions. https://doi.org/10.1101/2023.06.05.543720

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