Department of Life Science, Graduate School of Arts and Science, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
ACS Synth Biol. 2020 Jul 17;9(7):1771-1780. doi: 10.1021/acssynbio.0c00137. Epub 2020 Jun 17.
DNA replication is one of the central functions of the cell. The complexity of modern DNA replication systems raises a question: is it possible to achieve a simpler continuous isothermal DNA replication using fewer proteins? Here, we searched such replication using an evolutionary approach. Through a long-term serial dilution experiment with phi29 DNA polymerase, we found that large repetitive DNAs spontaneously appear and continuously replicate. The repetitive sequence is critical for replication. Arbitrary sequences can replicate if they contain many repeats. We also demonstrated continuous DNA replication using expressed polymerase from the DNA for 10 rounds. This study revealed that continuous isothermal DNA replication can be achieved in a scheme simpler than that employed by modern organisms, providing an alternative strategy for simpler artificial cell synthesis and a clue to possible primitive forms of DNA replication.
DNA 复制是细胞的核心功能之一。现代 DNA 复制系统的复杂性引发了一个问题：是否可以使用更少的蛋白质实现更简单的连续等温 DNA 复制？在这里，我们通过进化方法搜索了这种复制。通过对 phi29 DNA 聚合酶进行长期的连续稀释实验，我们发现大的重复 DNA 会自发出现并持续复制。重复序列对于复制至关重要。如果含有许多重复序列，任意序列都可以复制。我们还使用来自该 DNA 的表达聚合酶进行了 10 轮连续 DNA 复制实验。这项研究表明，连续等温 DNA 复制可以在比现代生物更简单的方案中实现，为更简单的人工细胞合成提供了一种替代策略，并为可能的原始 DNA 复制形式提供了线索。
