Updated project metadata. Cross-linking of isotope-labelled RNA coupled with mass spectrometry (CLIR-MS) was used to study the interaction between the four RNA recognition motifs (RRMs) of the protein PTBP1 with the internal ribosome entry site (IRES) of encephalomyocarditis virus (EMCV). These results are a reanalysis of PXD005566, with a broader parameter set.