title: Dissecting the ubiquitin pathway by mass spectrometry.
abstract: Protein modification by ubiquitin is a central regulatory mechanism in eukaryotic cells. Recent proteomics developments in mass spectrometry enable systematic analysis of cellular components in the ubiquitin pathway. Here, we review the advances in analyzing ubiquitinated substrates, determining modified lysine residues, quantifying polyubiquitin chain topologies, as well as profiling deubiquitinating enzymes based on the activity. Moreover, proteomic approaches have been developed for probing the interactome of proteasome and for identifying proteins with ubiquitin-binding domains. Similar strategies have been applied on the studies of the modification by ubiquitin-like proteins as well. These strategies are discussed with respect to their advantages, limitations and potential improvements. While the utilization of current methodologies has rapidly expanded the scope of protein modification by the ubiquitin family, a more active role is anticipated in the functional studies with the emergence of quantitative mass spectrometry.
authors.affiliation: Department of Human Genetics, Center for Neurodegenerative Disease, Emory University, Atlanta, GA 30322, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
authors.forename: Junmin
authors.initials: J
authors.lastname: Peng
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods; D003546:Cysteine Endopeptidases / Q000378:metabolism; D013058:Mass Spectrometry / Q000379:methods*; D053858:Metabolic Networks and Pathways / Q000502:physiology; D045726:Metalloproteases / Q000378:metabolism; D025821:Polyubiquitin / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D040901:Proteomics / Q000379:methods*; D025842:SUMO-1 Protein / Q000378:metabolism; D053719:Tandem Mass Spectrometry / Q000379:methods; D025801:Ubiquitin / Q000378:metabolism*
chemical_list: D025842:SUMO-1 Protein; D025801:Ubiquitin; D025821:Polyubiquitin; D045726:Metalloproteases; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex