Using simple artificial cells, a research group led by Makito Miyazaki of the RIKEN Center for Integrative Medical Sciences (IMS) in Japan has uncovered fundamental physical principles that govern how living cells change their shape. By combining experiments with computer simulations and theoretical analysis conducted in collaboration with Purdue University, the researchers showed how a cell's actin cytoskeleton—the network of protein fibers that gives it its shape—can generate cell-scale shape changes and front-rear polarity without relying on complex biochemical signaling.