Fig. 4.
Correction of the ΔF508-CFTR defect following knockdown of FGF receptors and downstream signaling proteins. Average normalized fluorescence intensity of ΔF508-CFTR cells that were transfected with shRNA for A, FGFR2, B, FGFR3, C, Erk1, D, Erk2, E, Akt, F, PLC-γ1, G, FRS2. H, Quantitation of rescue (difference in average fluorescence intensity ΔFIavg) of the hits at 24 s after adding iodide solution. Data are mean ± S.E. from three independent experiments, each performed in triplicates (three fields per well, 70–300 cells per field). KD stands for knockdown efficiency (%). I, Immunoblot analysis for maturation of ΔF508-CFTR in 293MSR-GT cells (stably expressing ΔF508-CFTR) transfected with shRNA for FGFR1, 2, and 3, Erk1 and 2, Akt, PLC-γ1, or luciferase (nonsilencing control). 27 °C represents temperature rescue of ΔF508-CFTR at 27 °C, and WT CFTR represents wild-type CFTR. The 27 °C and WT CFTR lanes were loaded with a half of the amount of protein in comparison to the other analyzed samples. (J) Quantitation of rescue (increase in the band C/B ratio) of ΔF508-CFTR, following shRNA-mediated knockdown of the indicated signaling proteins.