Fig. 2: FRAP analysis of actin mobility in dendritic spines.

A Examples of FRAP experiments performed either without (top panels, control) or 30 minutes after cLTP induction (bottom panels, cLTP). The images show representative dendritic spines before fluorescence photobleaching (left panels, − 1 seconds), immediately afterwards (middle panels, 0 seconds) or after a recovery period (right panels, 280 seconds). B An analysis of the fluorescence recovery kinetics, indicated as means ± SEM (N = 16, 12, 9 and 11 spines for control and the cLTP experiments at increasing intervals as indicated by color; source data under51). Solid lines depict fitted double-exponential time-courses used for determining the stable fraction. C Bar graph of the the stable pool fractions in control as well as 30, 90 and 150 minutes after cLTP as measured by mean ± SEM of the immobile fractions obtained from the last 36 time points of the FRAP measurements in (B) (solid) and from a curve fit of the curves in (B) (transparent). The difference in the immobile fractions is significant (Kruskal-Wallis-test, p = 0.0056 with posthoc-Dunn-test p = 0.047, 0.008 and 0.047 for the three indicated significant differences).