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A large-scale resource, iMPAQT, provides multiple reaction monitoring (MRM)–mass spectrometry assays for targeted quantitative analysis of mTRAQ-labeled human proteins.
A newly developed algorithm enabled clustering of all 256 million (66 million identified and 190 million unidentified) peptide MS/MS spectra available in the PRIDE Archive database, allowing the detection of millions of consistently unidentified spectra across different data sets, of which roughly 20% could be identified using multiple complementary analysis tools.