Cells make a number of key decisions by actively applying forces to the objects that they ‘touch’, responding to the softness or stiffness of their microenvironment. Changes range from reorganization of the cell-skeleton to Active Nematic, Smectic or Isotropic states to major alterations in Nuclear Shape and Gene Expression. Experiments and simple models will be described that capture the essence of these phenomena in addressing the question how deeply cells feel.
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