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

ABSTRACT: 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

SUBMITTER: Curran TG 

PROVIDER: S-EPMC4293043 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature