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bioRxiv · 10.1101/421214

Thesaurus: quantifying phosphoprotein positional isomers

Searle, B. C.·Lawrence, R. T.·MacCoss, M. J.·Villen, J.
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Abstract

Proteins can be phosphorylated at neighboring sites resulting in different functional states, and studying the regulation of these sites has been challenging. Here we present Thesaurus, a search engine that detects new positional isomers using site-specific fragment ions from parallel reaction monitoring and data independent acquisition mass spectrometry experiments. We apply Thesaurus to analyze phosphorylation events in the PI3K/AKT signaling pathway and show neighboring sites with distinct quantitative profiles, indicating regulation by different kinases.

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Searle, B. C., Lawrence, R. T., MacCoss, M. J., Villen, J.. 2018-09-26. Thesaurus: quantifying phosphoprotein positional isomers. https://doi.org/10.1101/421214

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