Protein induced fluorescence enhancement (PIFE) for probing protein-nucleic acid interactions

Single molecule studies of protein-nucleic acid interactions shed light on molecular mechanisms and kinetics involved in protein binding, translocation, and unwinding of DNA and RNA substrates. In this review, we provide an overview of a single molecule fluorescence method, termed protein induced fluorescence enhancement'' (PIFE). Unlike FRET where two dyes are required, PIFE employs a single dye attached to DNA or RNA to which an unlabeled protein is applied. We discuss both ensemble and single molecule studies in which PIFE was utilized.