The present invention relates to a method for identifying a binding site on an RNA transcript, wherein the binding site binds to one or more binding moieties. The method includes, among other things, introducing a photoreactive nucleoside into living cells wherein the living cells incorporate the photoreactive nucleoside into RNA transcripts during transcription thereby producing modified RNA transcripts; reverse transcribing the RNA of isolated cross-linked segments thereby generating cDNA transcripts with one mutation wherein the photoreactive nucleoside is transcribed to a mismatched deoxynucleoside; amplifying the cDNA transcripts thereby generating amplicons; and analyzing the sequences of the amplicons aligned against the reference sequence so as to identify the binding site, wherein the sequences of each amplicon having a mutation resulting from the introduction of the photoreactive nucleoside is considered to be a valid amplicon comprising at least a portion of a binding site on the RNA transcript.