Unveiling the unusual i-motif-derived architecture of a DNA aptamer exhibiting high affinity for influenza A virus
Scientists from IBCH RAS in collaboration with other institutes have established a unique structure of an aptamer to the hemagglutinin of the influenza A virus. The authors showed that the parent aptamer BV42, containing an extended cytosine tract, folded into i-motif, one of the non-canonical nucleic acid structures. However, the conformational heterogeneity of BV42 hindered detailed structural analysis. The use of computational methods and chemical modification helped to identify a potential binding site and apply a unique approach to eliminating conformational diversity while retaining high binding affinity. NMR spectroscopy confirmed the unique structure of the optimized aptamer, containing an i- motif and a duplex module with flexible junction. The results represent significant progress in the rational design of aptamers, highlighting the functional potential of DNA i-motifs for specific protein recognition under physiological conditions. The results are published in Nucleic Acids Research.
january 10