Regulation in the cellular slime molds

Studies of cellular differentiation in the developing cellular slime molds Dictyostelium discoideum (1), D. mucoroides (TYP), and a D. mucoroides mutant (MV) were conducted using fluorescent antisera. These antisera could distinguish between the major cell types, the prestalks and prespores, by their degree of staining. Consequently the differentiation of these cells could be followed during development. Dd and TYP migrating pseudoplasmodia were transected to obtain isolated prestalk and prespore masses. The reorganizing cell masses regained the antigenic patterns typical of the normal migrating pseudoplasmodia. The synthesis of antigen throughout an isolated prestalk mass suggested that it was necessary in the differentiation of prespore cells. Furthermore the data suggested that regulation of the proportions of prestalk and prespore cells is achieved by the interaction of the two cell types until an equilibrium is reached.