En route to dynamic life processes by SNARE-mediated fusion of polymer and hybrid membranes
Lado Otrin, Agata Witkowska, Nika Marušič, Ziliang Zhao, Rafael B. Lira, Fotis L. Kyrilis, Farzad Hamdi, Ivan Ivanov, Reinhard Lipowsky, Panagiotis L. Kastritis, Rumiana Dimova, Kai Sundmacher, Reinhard Jahn, Tanja Vidaković‐Koch
Abstract
A variety of artificial cells springs from the functionalization of liposomes with proteins. However, these models suffer from low durability without repair and replenishment mechanisms, which can be partly addressed by replacing the lipids with polymers. Yet natural membranes are also dynamically remodeled in multiple cellular processes. Here, we show that synthetic amphiphile membranes also undergo fusion, mediated by the protein machinery for synaptic secretion. We integrated fusogenic SNAREs in polymer and hybrid vesicles and observed efficient membrane and content mixing. We determined bending rigidity and pore edge tension as key parameters for fusion and described its plausible progression through cryo-EM snapshots. These findings demonstrate that dynamic membrane phenomena can be reconstituted in synthetic materials, thereby providing new tools for the assembly of synthetic protocells.