A collection of cutting-edge techniques for studying ubiquitin-dependent protein degradation via the proteasome. The topics covered range broadly from basic biochemistry to cellular assays to discovery techniques using mass spectrometric analysis. These biochemical and cellular methods are necessary to explore the ubiquitin-proteasome system and ubiquitin-proteasome-dependent functions. State-of-the-art and user-friendly, Ubiquitin-Proteasome Protocols offers novice and experienced bench scientists alike a thorough compendium of readily reproducible techniques that will accelerate discovery, enhance productivity, and permit manipulation of the system for varied research purposes.A collection of cutting-edge techniques for studying ubiquitin-dependent protein degradation via the proteasome. The topics covered range broadly from basic biochemistry to cellular assays to discovery techniques using mass spectrometric analysis. These biochemical and cellular methods are necessary to explore the ubiquitin-proteasome system and ubiquitin-proteasome-dependent functions. State-of-the-art and user-friendly, Ubiquitin-Proteasome Protocols offers novice and experienced bench scientists alike a thorough compendium of readily reproducible techniques that will accelerate discovery, enhance productivity, and permit manipulation of the system for varied research purposes.Part I. Biochemical Methods to Study the Ubiquitin-Proteasome SystemSmall-Molecule Inhibitors of Proteasome ActivityMaria Gaczynska and Pawel A. OsmulskiPurification of E1 and E1-Like EnzymesArthur L. HaasAssays for RING Family Ubiquitin LigasesManabu Furukawa, Paul S. Andrews, and Yue XiongUbiquitin Chain SynthesisShahri Raasi and Cecile M. PickartPurification of Proteasomes, Proteasome Subcomplexes, and Proteasome-Associated Proteins From Budding YeastDavid S. Leggett, Michael H. Glickman, and Daniel FinleyRecognition and Processing of Misfolded Proteins by PA700, the 19S Regulatory Complex of the 26S ProteasomeChal£*