Chemical oscillators have long been studied by engineers and scientists. The researchers who discovered the chemical oscillator that controls the human circadian rhythm — responsible for our bodies’ day and night rhythm — earned the 2017 Nobel Prize in physiology or medicine. In the new study, David Soloveichik and his research team in the Cockrell School of Engineering at The University of Texas at Austin show how to program synthetic oscillators and other systems by building molecules that follow specific instructions.
What type of molecules are these?
DNA (Deoxyribonucleic Acid) Molecules
David Soloveichik, an assistant professor in the Cockrell School’s Department of Electrical and Computer Engineering, along with Niranjan Srinivas, a graduate student at the California Institute of Technology, and the study’s co-authors, have successfully constructed a first-of-its-kind chemical oscillator that uses DNA components — and no proteins, enzymes or other cellular components — demonstrating that DNA alone is capable of complex behavior. According to the researchers, their discovery suggests that DNA can be much more than simply a passive molecule used solely to carry genetic information.
The team developed their new oscillator by building DNA molecules that have a specific programming language, producing a repeatable workflow that can generate other complex temporal patterns and respond to input chemical signals. They compiled their language down to precise interactions — a standard practice in the field of electronics but completely novel in biochemistry.
This new synthetic oscillator could one day be used in synthetic biology or in completely artificial cells, ensuring that certain processes happen in order. But oscillation is just one example of sophisticated molecular behavior. Looking beyond oscillators, this work opens the door for engineers to create more sophisticated molecular machines out of DNA. Depending on how the molecular machines are programmed, different behaviors could be generated, such as communication and signal processing, problem-solving and decision-making, control of motion, etc. — the kind of circuit computation generally attributed only to electronic circuits.