Fig. 3. Fluorescence recovery after photo bleaching (FRAP) analysis of GFP-tagged B23 and its CK2 phosphorylation mutants. Cells were transfected with GFP-expressing construct and subjected to photobleaching 24-36 hours post transfection. Five scans were taken before bleaching. An area in the nucleolus or a whole nucleolus was bleached with the 488 nm laser and the fluorescence recovery of the bleached spot was measured every 5 seconds. The normalized fluorescence recovery in the ROI at each time point after photobleaching was plotted against time. The t1/2s of recovery for the mutants and the wild type protein B23 are indicated in the figure. Error indicates s.d. of the mean for each fitted curve. At least eight datasets were analysed for each result.