Increasing membrane tension decreases miscibility temperatures; an experimental demonstration via micropipette aspiration.

It has been hypothesized that cytoskeletal tension prevents large-scale phase separation within cell plasma membranes. Here, we microaspirate giant unilamellar vesicles to determine the effect of mechanical stress on the liquid/liquid miscibility temperature of a membrane composed of a ternary lipid mixture. An increase in tension of 0.1 mN/m induces a decrease in miscibility temperature on the order of a few tenths of a degree K, which validates recent theoretical predictions.

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