Figure 8.

Darlin⁻ mutants have a defect in early development. Dictyostelium wild-type (B and D) and darlin⁻ (A and C) cells were allowed to grow to confluency on plastic Petri dishes. The media were then replaced by starvation buffer, and the cultures were photographed after 12 h. Wild-type cells formed large aggregation centers that congregated into organized streams of elongated cells. Darlin⁻ cells failed to form aggregation centers and streams. In addition these cells did not elongate to the same extent as wild-type cells. Bars: (A and B), 1 mm; (C and D), 0.2 mm. (E and F) Cells were plated on nonnutrient agar and allowed to undergo development at room temperature. The pictures were taken 24 h after plating. Wild-type (F) and control cells formed normal size slugs that differentiated into normal fruiting bodies (our unpublished observations). The darlin-null cells (E) formed very small aggregating centers that lead to the formation of very small slugs and fruiting bodies. Bar, 0.3 cm.