Research
Multiplexed Protein Quantitation in Saccharomyces cerevisiae Using Amine-reactive Isobaric Tagging Reagents*

https://doi.org/10.1074/mcp.M400129-MCP200Get rights and content
Under a Creative Commons license
open access

We describe here a multiplexed protein quantitation strategy that provides relative and absolute measurements of proteins in complex mixtures. At the core of this methodology is a multiplexed set of isobaric reagents that yield amine-derivatized peptides. The derivatized peptides are indistinguishable in MS, but exhibit intense low-mass MS/MS signature ions that support quantitation. In this study, we have examined the global protein expression of a wild-type yeast strain and the isogenic upf1Δ and xrn1Δ mutant strains that are defective in the nonsense-mediated mRNA decay and the general 5′ to 3′ decay pathways, respectively. We also demonstrate the use of 4-fold multiplexing to enable relative protein measurements simultaneously with determination of absolute levels of a target protein using synthetic isobaric peptide standards. We find that inactivation of Upf1p and Xrn1p causes common as well as unique effects on protein expression.

Cited by (0)

Published, MCP Papers in Press, September 22, 2004, DOI 10.1074/mcp.M400129-MCP200

*

Part of this work was supported by National Institutes of Health Grant GM27757 (to A. J.).

The on-line version of this manuscript (available at http://www.mcponline.org) contains supplemental material.