Stable isotope-free relative and absolute quantitation of protein phosphorylation stoichiometry by MS.

ABSTRACT: Qualitative and quantitative information are crucial to a detailed understanding of the function of protein phosphorylation. MS is now becoming a quantitative approach to analyze protein phosphorylation. All methods that have been described either require the elaborate/expensive use of stable isotopes to compare a limited number of samples or do not provide phosphorylation stoichiometries. Here, we present stable isotope-free MS strategies that allow relative and absolute quantitation of phosphorylation stoichiometries. By using the developed methods, we can normalize to robustly account for run-to-run variations and variations in amounts of starting material. This procedure monitors the unmodified proteolytic peptides derived from the protein of interest and identifies peptides that are s

SUBMITTER: Steen H 

PROVIDER: S-EPMC552780 | biostudies-literature | 2005 Mar

REPOSITORIES: biostudies-literature