Analysis of Ribosomal Protein S1 and Messenger Ribonucleic Acid (mRNA) Cross-links by ICPMS and LC-MS/MS

摘要

The mass spectrometric characterization of protein:RNA cross-links is challenging due to the heterogeneity of the sample and the physical and chemical properties of the cross-link components. Previously we used mass spectrometry to identify the ribosomal proteins cross-linked to a leaderless mRNA mimic, a necessary first step in understanding how leaderless mRNAs are recognized by the ribosome. To date, characterization of the sequence specific sites of these ribosomal protein cross-links has not been performed. Here, we are proceeding to identify these cross-linking sites by a combination of inductively coupled plasma mass spectrometry (ICPMS) and liquid chromatography tandem mass spectrometry (LC-MS/MS). This new analytical strategy benefits from our prior development of ICPMS-based selective detection of phosphorus and sulfur in the cross-link.