Self-organization of movement: from single cell polarity to multicellular swarms.

Cell movement requires long-range coordination of the cytoskeletal machinery that organizes cell morphogenesis. We have found that reciprocal interactions between biochemical signals and physical forces enable this long-range signal integration. Through a combination of optogenetic inputs, mechanical measurements, and mathematical modeling, we resolve a recent controversy regarding the role of membrane tension propagation in this process and reveal the requirements for long-range transmission of tension in cells. Most cells don't move in isolation-- they collectively migrate by sharing information similar to the flocking of birds, the schooling of fish, and the swarming of ants. We reveal a novel active signal relay system that rapidly and robustly ensures the proper level of immune cell recruitment to sites of injury and infection.