Phase transition of tensin-1 during the focal adhesion disassembly and cell division

Lee, Y.-R. J.; Yamada, S.; Lo, S. H.

doi:10.1101/2022.11.16.516818

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bioRxiv · 10.1101/2022.11.16.516818

Phase transition of tensin-1 during the focal adhesion disassembly and cell division

Lee, Y.-R. J.·Yamada, S.·Lo, S. H.

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Abstract

Biomolecular condensates are non-membranous structures that are mainly formed through liquid-liquid phase separation. Tensins are focal adhesion (FA) proteins linking the actin cytoskeleton to integrin receptors. Here we report that GFP-tagged tensin-1 (TNS1) proteins at physiological levels phase separate to form biomolecular condensates in TNS1 knockout cells. Live cell imaging showed that new TNS1 condensates are budding from the disassembling ends of FAs, and presence of these condensates is cell cycle dependent. TNS1 condensates dissolve immediately prior to mitosis and rapidly reappear while post-mitotic daughter cells establish new FAs. TNS1 condensates contain selected FA proteins and signaling molecules such as pT308Akt but not pS473Akt, suggesting previously unknown roles of TNS1 condensates in disassembling FAs, as the storage of core FA components and the signaling intermediates.

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Lee, Y.-R. J., Yamada, S., Lo, S. H.. 2022-11-17. Phase transition of tensin-1 during the focal adhesion disassembly and cell division. https://doi.org/10.1101/2022.11.16.516818

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