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bioRxiv · 10.1101/259341

Long-range Notch-mediated tissue patterning requires actomyosin contractility

Hunter, G.·He, L.·Perrimon, N.·Charras, G.·Giniger, E.·Baum, B.
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Abstract

Dynamic, actin-based protrusions function in cell-cell signaling in a variety of systems. In the dorsal thorax of the developing fly, basal protrusions enable non-neighboring epithelial cells to touch, extending the range over which Notch-mediated lateral inhibition can occur during bristle patterning. Given that actin-based cell protrusions can exert mechanical forces on their environment and Notch receptor activation is mechanically sensitive, how might cytoskeletal contractility contribute to Notch signaling? We identify a pool of basal non-muscle myosin II (myosin II) that regulates protrusion dynamics, promotes Notch signaling, and is required in signal sending and receiving cells for Notch-dependent patterning. We show that interactions between protrusions are extensive and subject to actomyosin contractility. The effects of reducing myosin II activity are more pronounced for protrusion-mediated signaling than for signaling at lateral cell contacts. Together, these results reveal a role for actomyosin contractility in Notch activation, signaling, and patterning in a developmental context.

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Hunter, G., He, L., Perrimon, N., Charras, G., Giniger, E., Baum, B.. 2018-02-02. Long-range Notch-mediated tissue patterning requires actomyosin contractility. https://doi.org/10.1101/259341

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