Figure 4
Molecular inactivation of cofilin with SuperNova.
(a) COS7 cells co-expressing actin-GFP and cofilin-SuperNova were made. The fluorescence image of actin-GFP and cofilin-SuperNova before and after CALI is shown. Bleaching of SuperNova's fluorescence was clearly observed after CALI. The dashed square in the actin-GFP image is the pseudopod region selected in time lapse imaging and analysis. Scale bar, 10 μm. (b) Still frames obtained during time lapse imaging of actin-GFP motion in lamellipodia before and after CALI by cofilin-SuperNova are shown. The numbers indicate time (min) after light irradiation (9.6 W/cm2, 1 min with through a 580AF20 from a mercury lamp). Scale bar, 10 μm. (c) Histograms of the temporal correlation in the cells expressing no fluorescent protein-tagged cofilin (NO, n = 14), cofilin-CFP (CFP, n = 20 cells), cofilin-KillerRed (n = 14 cells) and cofilin-SuperNova (n = 19 cells). Temporal correlation after CALI normalized by the pre-CALI value was represented as fold change in temporal correlation, which indicates the duration time of initial fluorescence pattern of actin-GFP. Therefore, a higher value reflects the slower movement. p < 0.001 for NO vs SuperNova, p > 0.10 for NO vs CFP, p = 0.083 for NO vs KillerRed, t-test.
