Using the Ubiquitin-modified Proteome to Monitor Protein Homeostasis Function

University of California, San Diego, United States.
Molecular &amp Cellular Proteomics (Impact Factor: 7.25). 05/2013; 12(12). DOI: 10.1074/mcp.R113.029744
Source: PubMed

ABSTRACT The ubiquitin system is essential for maintenance of proper protein homeostasis function across eukaryotic species. While the general enzymatic architecture for adding and removing ubiquitin from substrates is well defined, methods for the comprehensive investigation of cellular ubiquitylation targets have just started to emerge. Recent advances in ubiquitin modified peptide enrichment have greatly increased the number of identified endogenous ubiquitylation targets as well as the sites of ubiquitin attachment within these substrates. Herein we evaluate current strategies using mass spectrometry based proteomics to characterize ubiquitin and ubiquitin like modifications. Using existing data we describe the characteristics of the ubiquitin modified proteome and discuss strategies for biological interpretation of existing and future ubiquitin-based proteomic studies.

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