Cofilin 1 rescues the ciliary defects induced by NudC depletion, but not vice versa. (A-F) RPE-1 cells treated with the indicated RNAi and expression vectors and subjected to serum starvation are analyzed by western blotting and immunofluorescence. Cilia length is determined by Image J software. Ectopic expression of cofilin 1 reverses abnormal cilia elongation caused by NudC depletion (A, B). Exogenous expression of NudC fails to inhibit aberrant cilia elongation induced by cofilin 1 knockdown (C, D). Double depletion of NudC and cofilin 1 has no synergistic effect on cilia length (E, F). (G-L) RPE-1 cells treated with the indicated RNAi and expression vectors are analyzed by immunoblotting and immunostaining. Percentages of cells with cilia in different treatments are shown. Ectopic expression of cofilin 1 inhibits spontaneous ciliogenesis caused by NudC knockdown (G, H). Exogenous expression of NudC is unable to reverse spontaneous ciliogenesis induced by cofilin 1 depletion (I, J). NudC knockdown shows no synergistic effect with cofilin 1 depletion on ciliation (K, L). Quantitative data derived from at least three independent experiments are shown as mean ± SD. n, sample size. ***P < 0.001; ns, not significant (P > 0.05).