| Lun. 16/07/2012 15:00 rdc bat. 11|
Motor activity drives connected networks to a fragile critical state
Cells and tissues rely on cytoskeletal proteins like actin and myosin when moving, dividing, and changing shape. These proteins are small but together they exert pulling forces over length scales of whole cells and embryos. How can small myosin motors pull together over long distances? We answer this question by observing myosin-driven pulling in in-vitro model cytoskeletal networks. We quantify the length scale over which motors contract by image analysis and compare to percolation theory. Surprisingly, we find a broad range of parameter space that produces cluster sizes exhibiting a power-law distribution, which suggests that motor activity drives networks to critical connectivity.