Fig. 6
From: Self-replication of DNA by its encoded proteins in liposome-based synthetic cells
A semisynthetic cell with implemented Φ29-based linear DNA replication. A prospective minimal cell, whose chassis is based on the PUREfrex protein factory encapsulated inside phospholipid vesicles, is represented with its essential functional modules. The transfer of information (black solid lines) from DNA to protein is executed by the PURE system. Dashed lines indicate catalysis reactions. The DNA replication module, whereby the linear genomic DNA is capped with the Φ29 TP protein (triangles) and is replicated by the Φ29 DNA synthesis machinery, has been implemented in this study (purple). Other subsystems include the regeneration of all PURE system components from their genes, the synthesis of phospholipids for the growth of the compartment, the expression of division proteins, and incorporation of transmembrane proteins (channels, transporters) to regulate the molecular diffusion with the external environment, in particular of energy-rich compounds. One challenge to realize a fully functional cell will be to efficiently interface and coordinate the different modules, something that could be fostered by DNA replication through random generation and in vitro selection of favorable phenotypic traits. Gene regulatory circuits (not depicted) could be implemented to orchestrate the expression dynamics of the different modules
