FRAP analysis of Cep120 dynamics at centrioles. (A) Western blot of lysates from NIH3T3 and a Cep120-GFP–expressing NIH3T3 stable cell line (NIH3T3::Cep120-GFP) probed with anti-Cep120 antibody. Numbers on the left indicate molecular mass of markers in kilodaltons. (B) NIH3T3::Cep120-GFP cells stained for GFP (green) and glutamylated tubulin (red). Insets are magnified images of the centrosome region. Bar, 10 µm. (C) Photobleaching and recovery of Cep120 and centrin. The top and middle panels show NIH3T3::Cep120-GFP cells, and the bottom panels show NIH3T3::centrin-GFP cells. Control cells (top row) were not photobleached. In all other cases, the indicated centrioles were photobleached and then were assessed at the indicated times after photobleaching. Arrows indicate the centrioles that were photobleached. Bar, 1 µm. (D–H) For each time point before and after photobleaching, the relative fluorescence intensity of centrioles is shown. Results are a mean of three cells per bleaching experiment (one cell for centrin-GFP control). Data are means ± SD.