Kinase activity-independent role of Gprk2 by enriching PI(4)P in vivo.

(A–C) Wing discs carrying gprk2 clones and expressing Flag-Gprk2WT, Flag-Gprk2ΔC, or Flag-Gprk2-PHOSBP by MS1096-Gal4 were immunostained for En and GFP. The gprk2 mutant clones were marked by the lack of GFP expression. Arrows indicate the mutant clones near the A/P boundary. (D–F’) Wing discs expressing Flag-Gprk2WT by the dorsal compartment-specific ap-Gal4 were treated with 100 μM PI(4)P (with 1:1 Carrier 3) and 0.1 μg/mL ecdysone in the M3 medium for 4 h and then immunostained for Smo, PI(4)P, and Flag. Dashed lines indicate the dorsal/ventral boundary marked by immunostaining with the anti-Flag antibody, which is not included here. Arrows indicate elevated levels of Smo and PI(4)P by the expression of Gprk2WT. (G–I) Wing discs expressing Flag-Gprk2ΔC by ap-Gal4 were treated with PI(4)P as described above. Dashed lines indicate the dorsal/ventral boundaries.