Figure 2.

The Spectrin cytoskeleton represses interommatidial cell number and Hippo target gene expression in parallel with Kibra

• A-F The eyeless FLP MARCM system was used to generate mutant eyes that also express UAS.RNAi targeting the Spectrin cytoskeleton. Pupal retinas were examined at 42–46 h after puparium formation (APF). Cell membranes were marked with Dlg staining. (A) Control pupal retina showing cone cells surrounded by interommatidial cells. (B) kibra mutant pupal retina displaying additional interommatidial cells. (C) Pupal retina expressing α-spectrin RNAi showing additional interommatidial cells. (D) kibra mutant pupal retinas expressing α-spectrin RNAi showing many additional interommatidial cells. (E, F) Clones of α-spectrin mutant cells (GFP negative) (E) and β_H-spectrin/karst mutant cells (GFP negative) (F) show extra interommatidial cells. Scale bars, 20 μm.
• G-K UAS.RNAi lines were driven with hh.Gal4 UAS.GFP for expression in the posterior compartment and contained the ex.lacZ reporter transgene. (G) Control wing showing a normal ex.lacZ expression pattern, which is low at the dorsal–ventral boundary but high in the proximal regions of the wing disc. (H) RNAi knock-down of α-Spectrin results in a mild up-regulation of ex.lacZ in the posterior compartment. (I) RNAi knock-down of kibra results in a mild up-regulation of ex.lacZ in the posterior compartment. (J) Dual RNAi knock-down of both α-spectrin and kibra results in enhanced up-regulation of ex.lacZ in the posterior compartment. (K) RNAi knock-down of hippo results in an up-regulation of ex.lacZ in the posterior compartment. Scale bars, 50 μm.