Fig. 8.

MAP4 negatively regulates cilium length. (A–D) RPE1 cells were treated with two different MAP4-specific siRNAs [siMAP4(1) and siMAP4(2)] or luciferase targeting siRNA (siLUC) as a control. Expression of MAP4 was analyzed by western blotting (A), using antibodies against MAP4 and α-tubulin (α-tub) as a control, and by immunofluorescence (B), using antibodies against acetylated tubulin (AcTub; green) and MAP4 (red). (C) The ability of siRNA-treated cells to form cilia was analyzed by immunofluorescence from images obtained as in B. (C) The effects of MAP4 siRNA on ciliogenesis were quantified as in Fig. 6 and expressed as normalized ciliogenesis. Statistical analysis was performed with the Student’s t-test. (D) The length of the cilia of siRNA-treated cells was measured as in Fig. 6 (n = 50). Statistical analysis was performed with the Fischer test. Scale bar: 5 µm.