Crystal Structures of Cyanine Fluorophores Stacked onto the End of Double-Stranded RNA.

ABSTRACT: The indodicarbocyanine fluorophores Cy3 and Cy5 are extensively used as donor-acceptor pairs in fluorescence resonance energy transfer experiments, especially those involving single molecules. When terminally attached to double-stranded nucleic acids via the 5' phosphate group these fluorophores stack onto the ends of the molecule. Knowledge of the positions of the fluorophores is critical to the interpretation of fluorescence resonance energy transfer data. The positions have been demonstrated for double-stranded (ds) DNA using NMR spectroscopy. Here, we have used x-ray crystallography to analyze the location of Cy3 and Cy5 on dsRNA, using complexes of an RNA stem-loop bound to L5 protein determined at 2.4 Å resolution. This confirms the tendency of both fluorophores to stack on the free

SUBMITTER: Liu Y 

PROVIDER: S-EPMC5768521 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature