Figure 8.

Localization of K7-null cells in slugs. Mutant cells (A) or AX2 cells (B) were labeled with a fluorescent dye for tracking within an aggregate consisting of 95% wild-type cells. The open triangles show that labeled K7-null cells are mostly absent form the anterior (A) portion of the slugs. The filled triangles show that AX2 cells are not excluded from the front of the slug and are evenly in the anterior and posterior (P) portions. The bright spot at the tip of the slugs in both mixtures is thought to be an artifact due to the fiberoptic properties of the slug (Fisher, 1997; Wallraff and Wallraff, 1997) and not to represent an accumulation of labeled cells. Bar, 0.5 mm.