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bioRxiv · 10.1101/2024.07.01.599542

Self-growing protocell models in aqueous two-phase system induced by internal DNA replication reaction

Minagawa, Y.·Yabuta, M.·Su'estugu, M.·Noji, H.
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Abstract

The bottom-up reconstitution of self-growing artificial cells is a critical milestone toward realizing autonomy and evolvability. However, building artificial cells that exhibit self-growth coupled with internal replication of gene-encoding DNA has not been achieved yet. Here, we report self-growing artificial cell models based on dextran-rich droplets in an aqueous two-phase system of poly(ethylene glycol) (PEG) and dextran (DEX). Motivated by the finding that DNA induces the generation of DEX-rich droplets, we integrated DNA amplification system with DEX-rich droplets, which exhibited active self-growth. We implemented the protocells with cell-free transcription-translation (TXTL) systems coupled with DNA amplification/replication, which also showed active self-growth. We also observed self-growth activity of protocells carrying a single copy of DNA. Considering the simplicities in terms of the chemical composition and the mechanism, these results underscore the potential of DEX droplets as a foundational platform for engineering protocells, giving implications for the emergence of protocells under prebiotic conditions.

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Minagawa, Y., Yabuta, M., Su'estugu, M., Noji, H.. 2024-07-02. Self-growing protocell models in aqueous two-phase system induced by internal DNA replication reaction. https://doi.org/10.1101/2024.07.01.599542

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