Figure 3.

ChtA cells form spores in chimeras with the wild type. Mutant cells labeled with an actin promoter expressing β-gal were mixed 1:10 with unlabeled wild type (DH1). A shows the presence of the mutant cells in the prespore zone of slugs, and B shows the movement to the spore mass several hours later. The top two arrows point to mutant cells in the spore mass and the lower arrow to basal disc cells, which are sometimes labeled.