Figure 4 |. I/O interface scheme for synthetic circuits.

Three main types of components are employed to convert input signals into output signals. Signal transducers like aptamers, riboswitches and ribozymes, detect the inputs (in forms of pH value, UV light, metal ions, small molecules, proteins and so on) and convert them into nucleic acid signal molecules. These DNA/RNA signals undergo information processing using DNA/RNA-based circuitry. Following processing, signals are generated through transcription, translation or DNA lithography and output (in the form of fluorescence, protein products, a coded pattern and so on) from the circuit.