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bioRxiv · 10.1101/563353

Optogenetic control of cell morphogenesis on protein micropatterns

Zieske, K.·Mullins, R. D.
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Abstract

Cell morphogenesis is critical for embryonic development, tissue formation, and wound healing. Our ability to manipulate endogenous mechanisms to control cell shape, however, remains limited. Here we combined surface micropatterning of adhesion molecules with optogenetic activation of intracellular signaling pathways to control the nature and morphology of cellular protrusions. We employed geometry-dependent pre-organization of cytoskeletal structures together with acute activation of signaling pathways that control actin assembly to create a tool capable of generating membrane protrusions at defined cellular locations. Further, we find that the size of microfabricated patterns of adhesion molecules influences the molecular mechanism of cell protrusion: larger patterns enable cells to create actin-filled lamellipodia while smaller patterns promote formation of spherical blebs. Optogenetic perturbation of signaling pathways in these cells changes the size of blebs and convert them into lamellipodia. Our results demonstrate how the coordinated manipulation of adhesion geometry and cytoskeletal dynamics can be used to control membrane protrusion and cell morphogenesis.

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Zieske, K., Mullins, R. D.. 2019-03-04. Optogenetic control of cell morphogenesis on protein micropatterns. https://doi.org/10.1101/563353

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