SYANAC: SYnthetic biological Automaton for Noughts and Crosses

The project of Tokyo Alliance was to construct a bacterial system which plays 'noughts and crosses' against a human player. We named it SYANAC, SYnthetic biological Automaton for Noughts And Crosses. An unbeaten strategy of the game could be written in a simple state transition diagram with at most three turns. Based on the diagram, we tried to construct a set of in vivo logic gates which determines a move of SYANAC against that of the human player. For the logic gates, inputs are chemicals that regulate protein bindings to corresponding DNA sequences in reporter genes. In order to implement the logic gates efficiently, we standardised the protein-binding sequences and designed a systematic construction method. With the method, it is practical to combine some of these standardised sequences together to construct transcriptional regulatory regions. Since these protein-binding sites are short, we can use chemically synthesised DNA as a part. A regulatable gene was constructed by insertion of a -35/-10 promoter part and LacI-binding-site parts into a promoterless reporter plasmid which can also accommodate canonical Biobricks. This new method, thus, will allow us to construct a set of logic gates by combining standardised protein-binding parts and Biobricks and to realise the game.