title: Sustainable proliferation of liposomes compatible with inner RNA replication.
abstract: Although challenging, the construction of a life-like compartment via a bottom-up approach can increase our understanding of life and protocells. The sustainable replication of genome information and the proliferation of phospholipid vesicles are requisites for reconstituting cell growth. However, although the replication of DNA or RNA has been developed in phospholipid vesicles, the sustainable proliferation of phospholipid vesicles has remained difficult to achieve. Here, we demonstrate the sustainable proliferation of liposomes that replicate RNA within them. Nutrients for RNA replication and membranes for liposome proliferation were combined by using a modified freeze-thaw technique. These liposomes showed fusion and fission compatible with RNA replication and distribution to daughter liposomes. The RNAs in daughter liposomes were repeatedly used as templates in the next RNA replication and were distributed to granddaughter liposomes. Liposome proliferation was achieved by 10 cycles of iterative culture operation. Therefore, we propose the use of culturable liposomes as an advanced protocell model with the implication that the concurrent supplement of both the membrane material and the nutrients of inner reactions might have enabled protocells to grow sustainably.
authors.affiliation: Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan;
authors.forename: Gakushi
authors.initials: G
authors.lastname: Tsuji
authors.affiliation: Dynamical Micro-Scale Reaction Environment Project, Exploratory Research for Advanced Technology, Japan Science and Technology, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan; Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan;
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fujii
authors.affiliation: Dynamical Micro-Scale Reaction Environment Project, Exploratory Research for Advanced Technology, Japan Science and Technology, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan; Institute for Academic initiatives, Osaka University, 1-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sunami
authors.affiliation: Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan; Dynamical Micro-Scale Reaction Environment Project, Exploratory Research for Advanced Technology, Japan Science and Technology, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan; Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan; yomo@ist.osaka-u.ac.jp.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yomo
mesh_terms: D005615:Freezing; D008055:Lipids / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D012313:RNA / Q000737:chemistry*; D013696:Temperature
chemical_list: D008055:Lipids; D008081:Liposomes; D012313:RNA
keywords: flow cytometry; freeze–thaw; liposome fusion; protocell