Figure 3. CG13343 negatively regulates CiFL stability and Hh signaling.

(A–C) Stabilization of CiFL (A), induction of Hh signaling reporter dpp-lacZ (B) and Col protein (C) abutting the a/p boundary (indicated by the dashed line in A) in wing discs correlate with low-, intermediate- and high-threshold Hh signaling activity, respectively. Box brackets mark the dorsal compartment of wing discs where MS1096-Gal4 exhibits a much higher activity (also see Figure S1C). (D–O) CG13343 negatively regulates Hh signaling. RNAi knockdown of CG13343 in the dorsal compartment of the wing disc (box bracket) led to accumulation of CiFL protein (D) and expansion of dpp-lacZ activity (E). Similarly, CiFL stabilization (G) and ectopic Col expression (J) were observed in CG13343 RNAi-overexpressing cells (positively marked by mCD8-GFP in H and K) in anterior clones (G–L, arrowheads), but not in posterior clones (arrow). Ectopic Col activation was also evident in CG13343^SH2028 somatic clones (negatively marked by nGFP in N) located in the anterior compartment of the wing disc (M, arrowheads). Note that Ci and Col are not expressed in posterior cells.