MARQUIS: A multiplex method for absolute quantification of peptides and posttranslational modifications

• Main Authors: Curran, Timothy G. (Contributor), Zhang, Yi (Author), Ma, Daniel J. (Author), Sarkaria, Jann N. (Author), White, Forest M. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Biological Engineering (Contributor), Koch Institute for Integrative Cancer Research at MIT (Contributor)
• Format: Article
• Language: English
• Published: Nature Publishing Group, 2015-10-30T18:34:23Z.
• Subjects: Article
• Online Access: Get fulltext

 Absolute quantification of protein expression and posttranslational modifications by mass spectrometry has been challenging due to a variety of factors, including the potentially large dynamic range of phosphorylation response. To address these issues, we have developed MARQUIS-Multiplex Absolute Regressed Quantification with Internal Standards-a novel mass spectrometry-based approach using a combination of isobaric tags and heavy-labelled standard peptides, to construct internal standard curves for peptides derived from key nodes in signal transduction networks. We applied MARQUIS to quantify phosphorylation dynamics within the ​EGFR network at multiple time points following stimulation with several ligands, enabling a quantitative comparison of ​EGFR phosphorylation sites and demonstrating that receptor phosphorylation is qualitatively similar but quantitatively distinct for each ​EGFR ligand tested. MARQUIS was also applied to quantify the effect of ​EGFR kinase inhibition on glioblastoma patient-derived xenografts. MARQUIS is a versatile method, broadly applicable and extendable to multiple mass spectrometric platforms.