ABSTRACT
The RNA promoter region of the influenzaâ A virus has recently attracted much attention as an RNA target for the development of anti-influenza drugs. However, there are very few reports on small RNA-binding ligands targeting this region. In this work, it is reported that TO-PRO-3, a thiazole orange analogue with a trimethine bridge, exhibits strong and selective binding to the internal loop structure of the influenzaâ A virus RNA promoter. This binding accompanies the remarkable light-up response of TO-PRO-3 in the deep-red spectral region. By virtue of these binding and fluorescence signaling functions, TO-PRO-3 can act as a useful indicator for the assessment of the binding capabilities of various test compounds for this RNA region, with a view toward the development of anti-influenza drug candidates.
Subject(s)
Carbocyanines/chemistry , Influenza A virus/genetics , Promoter Regions, Genetic/genetics , RNA, Viral/genetics , Base Sequence , Binding Sites/genetics , Carbocyanines/metabolism , Carbocyanines/pharmacology , Fluorescence , Humans , Influenza A virus/drug effects , Influenza A virus/physiology , Influenza, Human/drug therapy , Influenza, Human/metabolism , Influenza, Human/virology , Molecular Structure , RNA, Viral/metabolism , Signal Transduction , Spectrometry, FluorescenceABSTRACT
We report that TO-PRO-3, a thiazole orange analogue with a trimethine bridge, functions as a deep-red fluorescent indicator for the internal loop structure of the bacterial (Escherichia coli) ribosomal decoding region of the aminoacyl-tRNA site (A-site), which enables the assessment of A-site binding capability of various test compounds including blue and even-green-emitting compounds.
