서강대학교

초록/요약

In biochemistry research, creating and fully understanding cellular structures and activities has always been one of the primary research interests. Investigations related to the mechanisms underlying the actions of various structural components and associated machinery widely use artificial cellular models. In particular, the physical cellular membrane-cytoskeleton interactions are essential in defining the morphology and its motility of living organisms. We developed the cell mimics, enclosed with one of the cytoskeleton proteins (F-actins). These systems to quantify the forces involved in actin polymerization and to resolve spatially the forces exerted in different membrane regions. These filaments successfully assembled into micron-sized, rigid bundles that adhered to and deformed the surface of the vesicle, consequently inducing the morphological change of the artificial cell via membrane-cytoskeleton interaction. Here, we built several differently conditioned giant unilamellar vesicles (GUVs) to control the actin-membrane interactions. Depending on the phases of the GUVs, ordered/disordered phases from saturated/unsaturated lipids, the GUVs exhibited a range of attraction-repulsion interactions with actin filaments. As we triggered the actin polymerization, the GUVs showed three different morphologies: phase-separated, Lo phase deprived, mixed-phase. Each GUVs morphologies showed different actin-membrane interactions: strong interaction, inner crust, no interaction. Through manipulating the actin-membrane interaction by lipid phase-separation, we could succeed in implementing artificial cells with morphological dynamics toward cellular motilities.