posted on 2024-02-22, 22:29authored byChristophe Lachance-Brais, Chihyu Yao, Alicia Reyes-Valenzuela, Jathavan Asohan, Elizabeth Guettler, Hanadi F. Sleiman
Nucleases present a formidable barrier
to the application of nucleic
acids in biology, significantly reducing the lifetime of nucleic acid-based
drugs. Here, we develop a novel methodology to protect DNA and RNA
from nucleases by reconfiguring their supramolecular structure through
the addition of a nucleobase mimic, cyanuric acid. In the presence
of cyanuric acid, polyadenine strands assemble into triple helical
fibers known as the polyA/CA motif. We report that this motif is exceptionally
resistant to nucleases, with the constituent strands surviving for
up to 1 month in the presence of serum. The conferred stability extends
to adjacent non-polyA sequences, albeit with diminishing returns relative
to their polyA sections due to hypothesized steric clashes. We introduce
a strategy to regenerate stability through the introduction of free
polyA strands or positively charged amino side chains, enhancing the
stability of sequences of varied lengths. The proposed protection
mechanism involves enzyme failure to recognize the unnatural polyA/CA
motif, coupled with the motif’s propensity to form long, bundling
supramolecular fibers. The methodology provides a fundamentally new
mechanism to protect nucleic acids from degradation using a supramolecular
approach and increases lifetime in serum to days, weeks, or months.