Discovering RNA-protein interactions: A library of photoMet-containing peptides was synthesized by using an Arg- and Leu-rich alpha-helical amphiphilic peptide. Irradiation of mixtures of these peptides and Rev-responsive element (RRE) hairpin RNA promoted formation of covalent adducts. Analysis of one adduct showed that U26 in the bulged stem is responsible for covalent bond formation with the carbene intermediate. This strategy can provide important structural information about RNA-peptide interactions.