Novel Technology Enables Reversible DNA Crosslinking

DNA traditionally functions as genetic material, storing and transmitting biological information through its base sequence. Recent developments show DNA can also serve as a molecular scaffold, using its programmable structure and base-pairing to position chemicals for selective reactions. This shifts DNA from passive information carrier to active participant in chemical processes, supporting advances in molecular engineering and nucleic acid technologies. 

Researchers at Tohoku University's Institute of Multidisciplinary Research for Advanced Materials have developed a new technology that uses the light-responsive artificial nucleic acid thioguanosine (TG) to achieve efficient interstrand DNA crosslinking. Crosslinking triggers via light irradiation or mild chemical oxidants while preserving the native double-helical structure. The team discovered thioguanosine's photoinduced reactivity, identifying an electron-transfer mechanism within DNA duplexes.

"There are many things that make this crosslinked DNA special, such as its high thermal stability and the fact that the crosslinks can easily be connected and disconnected," says Kazumitsu Onizuka, co-author of the study published in Communications Chemistry. "We have a lot of control over how the DNA is connected, which allows us to consistently produce a desired outcome in chemical reactions."

Reversibility represents a core feature. Redox switching or light activation breaks crosslinks without altering DNA structure, balancing stability with dynamic control. This property fits applications such as stimuli-responsive materials, intracellular drug delivery systems, and nucleic acid function studies.

The work establishes design principles and reaction mechanisms, expanding nucleic acid chemistry tools. Thioguanosine-based, proximity-driven, light-activated crosslinking provides a platform for reversible DNA modification. These capabilities support bionanomaterials including responsive drug delivery, programmable nanostructures, and DNA nanomachines for nanotechnology and medical applications.