http://www.rsc.org – Mechanical forces play an essential role in cellular processes as input, output, and signals. Various protein complexes in the cell are designed to handle, transform and use such forces. For instance, proteins of muscle and the extracellular matrix can withstand considerable stretching forces, hearing-related and mechanosensory proteins can transform weak mechanical stimuli into electrical signals, and regulatory proteins are suited to forcing DNA into loops to control gene expression. Read more »

http://www.pnas.org – A key molecular link between cells and the extracellular matrix is the binding between fibronectin and integrins α5β1 and αvβ3. However, the roles of these different integrins in establishing adhesion remain unclear. We tested the adhesion strength of fibronectin-integrin-cytoskeleton linkages by applying physiological nanonewton forces to fibronectin-coated magnetic beads bound to cells. We report that the clustering of fibronectin domains within 40 nm led to integrin α5β1 recruitment, and increased the ability to sustain force by over six-fold. Read more »