DNA-based nanodevices for detecting nerve disorders
doi:10.1038/nindia.2019.95 Published online 22 July 2019
Rare-earth elements could induce structural and conformational changes in self-assembled branched DNA structures that are found in cells1, researchers have discovered. Using a salt of lanthanide, a rare-earth element, they converted right-handed B-DNA to left-handed Z-DNA.
Since Z-DNA has roles in various human diseases such as blood cancer, autoimmune disorders and Alzheimer’s disease, it could be used as components for designing nanodevices for diagnostic and therapeutic purposes.
Previous studies had shown that when metal ions bind to branched DNA structures, they undergo structural changes, triggering conversion such as B-DNA to Z-DNA. However, the mechanism of such conversion is not yet known.
To shed further light on this conversion, scientists from the CSIR-Institute of Minerals & Materials Technology in Bhubaneswar, India, produced Z-DNA by adding lanthanide salts to a series of self-assembled branched DNA nanostructures.
The researchers, led by Umakanta Subudhi, found that the presence of a specific loop in the branched DNA structures contributed remarkably to their conformational flexibility and sensitivity, causing the transition from right-handed to left-handed DNA.
The formation of Z-DNA is sensitive even to two nucleotide changes in its structure. Such a property can be exploited to develop sequence- and salt-dependent biosensors and nanodevices.
Since the conformational change from B-DNA to Z-DNA controls specific biochemical pathways, such model DNA structures would be useful for developing novel therapies for various diseases, including nerve disorders, says Subudhi.
1. Bhanjadeo, M. M. et al. Sequence-specific B-to-Z transition in self-assembled DNA: A biophysical and thermodynamic study. Int. J. Biol. Macromol. 137, 337-345 (2019)