Cell differentiation through tissue elasticity-coupled, myosin-driven remodeling

Abstract

Cells may lack eyes to see and ears to hear, but cells do seem to have a sense of 'touch' that allows them to feel their microenvironment. This is achieved in part through contractility coupled adhesion to physically flexible 'soft' tissue. Here we summarize some of the known variations in elasticity of solid tissue and review some of the long-term effects of cells 'feeling' this elasticity, focusing on differentiation processes of both committed cell types and stem cells. We then highlight what is known of molecular remodeling in cells under stress on short time scales. Key roles for forces generated by ubiquitous and essential myosin-II motors in feedback remodeling are emphasized throughout.

Figure 1

Tissue elasticity scale (A) and model elastic culture systems (B).

Figure 2

Matrix elasticity effects on differentiation of committed cells (A) and mesenchymal stem cells (B).

Figure 3

Schematic of how myosin forces strain the cell and also strain the matrix as resisted by matrix elasticity. The strain within the cell is manifested as protein extension, domain unfolding, and/or protein-protein dissociation. These processes might simply relieve stress in the cell, or they might create sites for new binding partners or new signals.