Fluorescence detection of intron lariat RNA with reduction-triggered fluorescent probes

Fluorescence through proximity: Reduction-triggered fluorescent probes bearing either a fluorescein derivative or triphenylphosphine bind sequence-specifically at the branch site of lariat RNA. The chemical reaction between the two substrates leads to the formation of unquenched fluorescein and the emission of a fluorescence signal (see picture). Prelariat and lariat structures can be distinguished by using this method.