Novel artificial genomic DNA can replicate and evolve outside the cell

Professor Norikazu Ichihashi and his colleagues at the University of Tokyo have successfully induced gene expression from a DNA, characteristic of all life, and evolution through continuous replication extracellularly using cell-free materials alone, such as nucleic acids and proteins for the first time.

The ability to proliferate and evolve is one of the defining characteristics of living organisms. However, no artificial materials with these characteristics have been created. To date, it has been impossible to create a reaction system in which the genes necessary for DNA replication are expressed while those genes simultaneously carry out their function.

The group succeeded in translating the genes into proteins and replicating the original circular DNA with the translated proteins by using a circular DNA carrying two genes necessary for DNA replication (artificial genomic DNA) and a cell-free transcription-translation system. Furthermore, they also successfully improved the DNA to evolve to a DNA with a 10-fold increase in replication efficiency by continuing this DNA replication cycle for about 60 days.

By adding the genes necessary for transcription and translation to the artificial genomic DNA developed by the group, it could be possible to develop artificial cells that can grow autonomously simply by feeding them low-molecular-weight compounds such as amino acids and nucleotides, in the future. If such artificial cells can be created, we can expect that useful substances currently produced using living organisms (such as substances for drug development and food production) will become more stable and easier to control.