A computer simulation of pulsatile aggregation in Dictyostelium discoideum

A computer simulation is used to examine how the observed individual features of cellular behavior can be combined into a quantitatively consistent representation of the spatially and temporally periodic aggregative pattern found in Dictyostelium. The (one-dimensional) simulation incorporates such features as secretion delays and refractory periods, movement steps generated by superthresholdattractant derivatives sensed by extending pseudopods, and attractant diffusion and hydrolysis. Parameters are taken as far as possible from the experimental literature, but there are a number of uncertain areas where various alternatives are tried. Among the principal issues discussed are the length of secretion and the duration of the chemotactic signal.