Multifaceted nucleic acid probing with a rationally upgraded molecular rotor

Probing the sequence alterations, structures, interactions, and other important aspects of nucleic acids serves as the cornerstone of understanding nucleic acid-mediated biology and etiology, as well as the development of nucleic acid-based therapeutics. New strategies capable of accommodating these imperatives without necessitating specialized instrument or skills and potentially complementing existing methods are highly desired. Herein, we describe a rationally designed molecular rotor CCVJ-H ((9-(2-carboxy-2-cyanovinyl)julolidine-hydrazide)) and its superior performances compared to the universal base excision reporter probe CCVJ-1 in applications such as nucleic acid detection and DNA glycosylase assays. Furthermore, we showcase that the CCVJ-H probe accurately profiles the interactions between nucleic acids and small molecules, providing binding affinity and binding site information in a single reaction. We subsequently demonstrate the feasibility of applying the CCVJ-H system in high-throughput screening to identify nucleic acid-binding small molecules such as DNA CTG repeat expansion binders, potentially providing therapeutic interventions for myotonic dystrophy type 1. Finally, we profile the recognition difference between DNA/DNA and DNA/RNA against a library of small molecules, uncovering two drug-like molecules that preferentially bind DNA/RNA. We anticipate the versatile CCVJ-H probe will be a useful tool for both fundamental and translational nucleic acid research and application.