Dynamic interactions between microtubules and artificial membranes

We report that extensive adsorption of microtubule protein to liposomes occurs above the transition temperature of the phospholipid bilayer, occurs to phosphatidylcholine (PC) or phosphatidylserine (PS) vesicles, and is not affected by preincubation of microtubule protein with colchicine. Most importantly, we show that 51-63% of the tubulin adsorbed onto neutral (PC) phospholipid vesicles can be desorbed to form microtubules when buffer conditions are adjusted to favor microtubule assembly. By contrast, no microtubule assembly occurred with preadsorption of microtubule protein onto acidic (PS) phospholipid vesicles, suggesting irreversible binding.