The development of sporulation competence in Physarum polycephalum.

Plasmodial cells of the slime mold Physarum polycephalum become “competent” for sporulation following a prolonged period of dark starvation in the presence of nicotinamide. Sporulation can then be induced by illumination. Plasmodia are found to release into the medium during starvation one or more cellular products that promote sporulation. These products exert their effect specifically during the dark starvation period, rather than during the final phase of fruiting body construction. The sporulation control factor(s) (SCF) is nondialyzable and can stimulate the development of sporulation competence in the absence of nicotinamide.