COMPUTATIONAL MODELING OF MOUND DEVELOPMENT IN DICTYOSTELIUM

One of the structures seen during the course of Dictyostelium discoide um development is the loose aggregate or early mound structure. In thi s work, we attempt to simulate the formation of this three-dimensional mound by a model which incorporates cAMP chemical signaling and resul tant cell motions due to chemotaxis. Simulation results are compared t o measurements of the mound morphology as determined by confocal fluor escence microscopy. Good agreement is obtained only if the cells exhib it an adaptive response to high cell density and change their basic mo tion patterns. We argue that in the actual biological system, this occ urs because the high resting value of cAMP in the mound can effectivel y saturate the high-affinity receptors responsible for aggregation sta ge dynamics. Tests of our ideas using mutant cell lines are briefly di scussed.