Researchers have demonstrated that they can control how frequently a DNA-based nanodevice changes between two forms. Their "nanometronome" is the first example of such control over a single DNA molecule, the team contends.
The device consists of four strands of DNA, which in water assemble into a clover-shape structure. In the presence of magnesium ions, the assembly randomly switches between two stable, X-shaped forms, each with different strands paired into helices. The "ticking" rate between the two forms is mere milliseconds, the team reports.