Transport of actin-decorated liposomes along myosin molecules in vitro

We examined whether actin filaments bound to positively charged liposomes could interact with myosin molecules and induce liposome motility. When liposomes were constructed from the mixture of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and cationic N-[1-(2,3-Dioleoyloxy)propyl]-N,N,N-trimethylammonium (DOTAP), actin filaments bound to the liposomes. The actin-bound liposomes exhibited movement on myosin molecules in the presence of adenosine-5'-triphosphate (ATP). The displacement was almost linearly increased with time and the behavior differed from that of Brownian motion. Furthermore, the presence of 30% DOTAP in liposomes was most effective for transport. These data show that the actomyosin system was successfully integrated into the liposomes and possesses the ability to actively transport useful agents enclosed within the liposomes.