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Rapid RNA exchange in aqueous two-phase system and coacervate droplets.

ABSTRACT: Compartmentalization in a prebiotic setting is an important aspect of early cell formation and is crucial for the development of an artificial protocell system that effectively couples genotype and phenotype. Aqueous two-phase systems (ATPSs) and complex coacervates are phase separation phenomena that lead to the selective partitioning of biomolecules and have recently been proposed as membrane-free protocell models. We show in this study through fluorescence recovery after photobleaching (FRAP) microscopy that despite the ability of such systems to effectively concentrate RNA, there is a high rate of RNA exchange between phases in dextran/polyethylene glycol ATPS and ATP/poly-L-lysine coacervate droplets. In contrast to fatty acid vesicles, these systems would not allow effective segregation and consequent evolution of RNA, thus rendering these systems ineffective as model protocells.

SUBMITTER: Jia TZ

PROVIDER: S-EPMC4141154 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Rapid RNA exchange in aqueous two-phase system and coacervate droplets.

Jia Tony Z TZ Hentrich Christian C Szostak Jack W JW

Origins of life and evolution of the biosphere : the journal of the International Society for the Study of the Origin of Life 20140228 1

Compartmentalization in a prebiotic setting is an important aspect of early cell formation and is crucial for the development of an artificial protocell system that effectively couples genotype and phenotype. Aqueous two-phase systems (ATPSs) and complex coacervates are phase separation phenomena that lead to the selective partitioning of biomolecules and have recently been proposed as membrane-free protocell models. We show in this study through fluorescence recovery after photobleaching (FRAP) ...[more]

PMID: 24577897

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