Fig. 5.

Membrane dynamic elasticity. (A) Retraction process of tethers pulled from a POPC GUV after 0, 10, 13, 17, and 25 min of peptide addition. The solid lines represent fits to the data using $L=L_0\exp (\frac{-t}{\tau }$), where $\tau$ is the characteristic time. Inset: accumulated images obtained using DIC showing the bead motion (24 frames/s) after the laser was switched off. Left: without peptide, right: after 17 min of MP1 addition, note the slower bead motion and the loss of vesicle contrast due to the increased permeability. (B) Characteristic times $\tau$ as a function of time after the addition of 0.6 µM peptide to different GUVs composed of POPC + 20% CHO (each symbol correspond to a single GUV) (C) Characteristic times $\tau$ as a function of time after the addition of 0.6 µM peptide to GUVs composed of POPC (black), POPC + 20% DP (olive), POPC + 40% CHO (cyan) or DP (green). Data correspond to the average ($\pm$ SD) of at least 5 GUVs from at least two independent experiments. * and ** indicate significant statistical differences between the values at the indicated times and at the start and end of the experiment determined by one-way ANOVA, Tukey’s test at $p<0.02$ or $p<0.002,$ respectively.