Fig. 1. Cuticular transformations caused by the ectopic expression of vg (A,C) and co-overexpression of wg^DN-vg (B,D) under the control of Dll-G4. Effects of vg ectopic overexpression on gene expression in the second pair of the legs driven by Dll-G4 (E-F). Lines indicate optical sections along the z-axis. Scale bars: 0.1 mm. (A) Ventral view of a transformed thorax with distal segments of first and second legs differentiating as wing blade (blue asterisk) and third legs as haltere (red asterisk). The broken red line separates anterior (a) from posterior (p) territories in transformed legs. (A1,A2) Transformed wing blade with dorsal (D) and ventral (V) regions. Arrowheads indicate veins. (A3) The arrowhead indicates a campaniform sensillae. (A4) Higher magnification of the wing margin in anteroposterior transition. (A5) Observe the histotypic differences between wing blade (blue asterisk) and haltere territories (red asterisk). (B) Ectopic co-expression of vg and a dominant-negative form of wg reduces the transformation phenotypes obtained with the ectopic expression of vg alone. (B1) Distal (D) (red arrowhead) and proximal (P) tarsal parts in the third pair of legs (red asterisk) at higher magnification. Distal segments (arrowhead indicates bracts) are shown in B2 and proximal segments (without bracts) in B3. (C) Ectopic expression of vg leads to transformation of antenna with anterior (a) and posterior (p) wing margin elements. The insets show the differentiation of wing margin elements with anterior (a; C1,C2) and posterior (p; C1,C2) specifications. (D) Transformation in the antenna is reduced by the co-expression of vg and a dominant-negative form of wg. (E) Ectopic expression of vg QE-lacZ (green) in the transformed legs. Notice repression of vg QE-lacZ report (green) in territories with high levels of wg expression (red). (F) Dorsal transformed territories in adult legs are correlated with ap (green) expression. Notice that the annular expression of ap-lacZ in the leg is modified: it is expanded in ventral territories but reduced (white arrowhead) in dorsal ones. The expression of wg (red) is activated at high levels in the border (wing margin) of ap expression. (G) Anterior and posterior specification in transformations denoted by the wild-type expression of en (green). The expression of wg-lacZ (red) corresponding to the wing margin appears in anterior as well as in posterior territories.

Return to article