Rapid assessment of Watson-Crick to Hoogsteen exchange in unlabeled DNA duplexes using high-power SELOPE imino ¹H CEST.

ABSTRACT: In duplex DNA, Watson-Crick A-T and G-C base pairs (bp's) exist in dynamic equilibrium with an alternative Hoogsteen conformation, which is low in abundance and short-lived. Measuring how the Hoogsteen dynamics varies across different DNA sequences, structural contexts and physiological conditions is key for identifying potential Hoogsteen hot spots and for understanding the potential roles of Hoogsteen base pairs in DNA recognition and repair. However, such studies are hampered by the need to prepare 13C or 15N isotopically enriched DNA samples for NMR relaxation dispersion (RD) experiments. Here, using SELective Optimized Proton Experiments (SELOPE) 1H CEST experiments employing high-power radiofrequency fields (B1 > 250 Hz) targeting imino protons, we demonstrate accurate and robust cha

SUBMITTER: Liu B 

PROVIDER: S-EPMC10539785 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature