Fig. 5. Ras mutant cells do not participate in dorsal appendage formation. (A-D) Bright-field and confocal images of dissected stage 14 eggs with associated Ras follicle cell clones. Clones are identified by their lack of myc expression (outlined in yellow). (A) Chorion nub on a mosaic eggshell (black arrowhead). The other appendage on this egg (a) extends out of the plane of focus. An appendage from an adjacent egg also extends into the field (white arrowhead). (B) Confocal image of the egg chamber in A. A Ras clone covers a large portion of the dorsal anterior portion of the egg chamber, but the chorion nub is made by wild-type, myc+ cells neighboring the Ras clone. (C) Enlargement of the box in B. The dark hole is filled with the chorion making up a nub, which was secreted by about 8 wild-type cells. Though not visible in this projection, these cells cover the entire nub. (D) Confocal projection of a mosaic egg chamber with ‘teardrop’-shaped chorion nub. A Ras clone resides to the anterior of the group of wild-type cells making the nub, and appears to block the progress of the migrating cells. (E) Confocal projection of the anterior tip of a stage 14 control egg chamber showing that control clone cells are capable of migrating to the full anterior extent (arrowhead).
