Fig. 2. Ras and Egfr are required cell-autonomously for dorsal repression of pipe-lacZ. Confocal projections of control (A), Ras^C40b (B,D,E), and Egfr^CO (C) follicle cell clones, marked by the absence of the myc epitope. Clones are outlined in yellow. pipe-lacZ expression was detected by ß-gal antibody. Anterior is to the left in all panels. (A) Dorsal view of a large control clone in which dorsal pipe-lacZ repression is unaffected. The posterior expression seen in this egg chamber is normal and is contiguous with the normal ventral region of pipe-lacZ expression (out of the plane of focus). Dorsal appendages from an adjacent S14 egg chamber abut the posterior half of this egg chamber. (B) pipe-lacZ is cell-autonomously derepressed in a dorsal Ras follicle cell clone. (C) Dorsolateral view of two Egfr clones: dorsal clone (top) and ventrolateral clone (bottom) both cell-autonomously derepress pipe-lacZ. (D,E) Lateral views of Ras mosaic egg chambers. In both egg chambers, the edge of the normal ventral and posterior domains of pipe-lacZ expression can be seen (small arrows), as can cell-autonomous pipe-lacZ derepression in the clones. (D) A patch of lateral follicle cells ventral/posterior to a large dorsal/lateral Ras clone still represses pipe-lacZ (large arrowhead). (E) Ventral pipe-lacZ expression spreads dorsally (large arrowhead) into the lateral region in this egg chamber with a dorsal Ras clone. This expansion, however, is also seen in wild-type (Fig. 1).