How surrogates for cortical forces determine cell shape

Recent experimental work has shown that numerous cell types can use different modes to move in different environments. Some cells crawl and some swim, but many can do both, and understanding how they interrogate their environment and determine how to move in response to information acquired is central to understanding basic processes ranging from early development to cancer metastasis. Cell movement usually involves shape changes, which are determined by both intra- and extracellular forces. Intracellular forces are transmitted to the membrane via tractions exerted on the membrane by the cell cortex, a thin composite of actin filaments, motor proteins and various linker proteins underlying the membrane, and herein we determine how surrogates for the normal and tangential components of cortical forces determine the shape of cells.