"How Do Cells Know Where to Go?"
James A. Glazier
Department of Physics
University of Notre Dame
Notre Dame, In 46556
Abstract
During embryonic development, cells need to migrate long distances through
tissues. How do they know where to go? Two basic mechanisms
are at work. Over long distances, cells secrete and follow
gradients of diffusible chemicals (chemotaxis). Once they are approximately
in the correct position, variable adhesion molecules expressed on their
surfaces help them to form coherent structures by energy minimization
(differential adhesion). A classic examples of chemotaxis is the
aggregation of amoebae in slime mold, of cell sorting, the reorganization
of a random clump of cells to form normal hydra. Failure of normal cell
sorting may play a role in cancer metastasis. Simulations and quantitative
experiments help disentangle these processes.