PCIF1 inhibits ciliogenesis in an m ⁶ Am-dependent manner. (A–C) RPE-1 cells treated with the indicated siRNAs for 24 h were transfected with control, PCIF1, or PCIF1-N553A plasmid for another 36 h under normal culture conditions, and then subjected to Western analysis or immunofluorescence. (D–F) RPE-1 cells transfected with the indicated plasmids for 48 h were treated with serum starvation for another 24 h and then applied for Western analysis or immunofluorescence. Western blotting analysis of PCIF1 protein (A and D). Actin is the internal control. Immunofluorescence images of RPE-1 cells with anti-ARL13B (green) and γ-tubulin (red) antibodies (B and E). DNA was stained with DAPI (blue). Cilia were indicated by white arrows. Scale bar, 10 μm. Quantitative analysis of the ciliation percentage is presented using SuperPlots (C and F). Each color within the SuperPlots signifies an independent biological replicate. Smaller symbols denote the ciliation percentage under each field of view, while larger symbols represent the mean value for each replicate. All error bars represent means ± SD. Student’s t test, **P < 0.01, ***P < 0.001, ns, not significant. Source data are available for this figure: SourceData F2.