Membrane tension is a recognized regulator of a wide range of cellular functions; however, whether it acts locally or globally in different contexts is the subject of lively debate. Recent experiments that perturb tension locally and measure the response elsewhere on the membrane have been inconclusive [1,2,3,4], and the mechanism of diffusive tension relaxation has recently been called into question [3].

In this talk I will present modeling work on the tension response of a suddenly extended membrane tether, a wide-spread probe of membrane-environment coupling. I will report the first testable prediction (to my knowledge) of cell membrane tension relaxation. Assuming tension relaxes diffusively, our model shows a self-similar (but non-classical) membrane response to tether extension. A corollary of this result is a prediction of power-law decay in time of the tether force, with a material-independent exponent of $\delta =1/3$. This prediction is confirmed by fitting our model to 11 sets of existing from two cell types [5, 6]. Remarkably, the best fit value of for each set is within a few percent of the theoretical prediction, suggesting that long range and fine structure-independent membranes flows relax tension perturbations.

[1] Shi, Z.,…, Cohen, A.E. (2018). Cell 175, 1769–1779.e13.

[2] Shi, Z., Innes-Gold, S., and Cohen, A.E. (2022). Sci. Adv. 8.

[3] Gomis Perez C, …Karatekin E (2022). Sci Adv 8, eabl4411.

[4] De Belly, H., … Weiner, O. (2023). Cell 186:3049–3061 e3015.

[5] Datar, A.,… Pullarkat, P. A. (2014). Biophys. J. 108, 489–497. 


[6] Pradhan,… Hale, T (2022). Biochem. Biophys. Res. Comm. 587, 126-130.