Chemotactic cell sorting in Dictyostelium discoideum.

We made mixed mounds of vitally stained prestalk cells and unstained prespore cells, from Dictyostelium discoideum (Dd), and exposed these to external 3',5'-cyclic-AMP (c-AMP) sources. We show that prestalk cells will sort out by moving directionally toward c-AMP sources held at less than 10(-5) M c-AMP. This is evidence for cell sorting via chemotaxis. We present arguments that the natural cell sorting, observed during Dd development, is also chemotactic to c-AMP.