Profilin intracellular levels modify actin treadmilling dynamics.

<p>A) Example of fluorescence recovery in a control MDA-MB-231 cell and after a 24 h treatment with PTD4-PfnI 3 µM. B) Plot summary of the average mobile fraction (left axis) and mean tau (right axis) values before (white box) and after PTD4-PfnI treatment (black box; n = 24). PTD4-PfnI caused a 29% reduction of the mobile fraction from 69±1% to 40±2% and increased the recovery time to a mean value of 8.2±2.2 s (p<0.05 and p<0.005; Student's t-test) C) Example of actin fluorescence recovery in a MDA-MB-231 cell transfected with GFP-PfnI (green) or MembraneCherry-PfnI (red) showing a similar effect to that of PTD4-PfnI treatment. D) Summary plot of the average mobile fraction (left axis) and mean recovery time (right axis). On average, transfection with GFP-PfnI reduced the mobile fraction to a mean value of 50±1.2% (n = 15), while it increased the time course of recovery to a mean value of 9.0±2.2 s. MmbCherry-PfnI expression reduced mobile fraction to 58±3% and slowed recovery time to 8.9±2.2 s (n = 15). (p<0.05 and p<0.005; Student's t-test).