Discovery of RNA-cleaving DNAzymes: Recent Advancements, New Functions and Practical Applications

RNA-cleaving DNAzymes (RCDs) are catalytic DNA molecules for RNA cleavage. RCDs offer many advantages. However, their broader application is limited by an incomplete understanding of RCD structures and catalytic mechanisms, and instability for use in biological environments. This review focuses on recent progress aimed at solving the challenges. We first introduce the fundamental basics of RCD, followed by recent advances in high-resolution structural studies and insights into catalytic mechanisms. Selection of non-8-17 RCDs with atypical structure is introduced. We next discuss emerging in vitro selection methods that expand RCD functionality, including selections under unconventional conditions and the use of chemically modified nucleotide libraries. Finally, we describe applications of RCDs in detecting site-specific RNA modifications, metal imaging, biosensing, disease biomarker detection, pathogen diagnostics, gene regulation, and logic gate construction, and conclude with perspectives on future research directions.