Direct measurement of species-specific cohesion in cellular slime molds.

Abstract

Partially differentiated cells of 2 spp. of cellular slime molds, Dictyostelium discoideum and D. purpureum, were labeled with isothiocyanate derivatives of fluorescent dyes. The labeled cells of each species segregated promptly when mixed and placed on moist filters. Whether cells studied at a time when they demonstrated this capacity to segregate showed a preferential adherence to cells of the same species was determined. When labeled dissociated cells of each species were interacted with an unlabeled immobilized layer of cells of each species under appropriate conditions, binding was, in part, species-specific.