title: Determination of proteasomal activities.
abstract: The proteasome is an important component of the intracellular system for the turnover of proteins. The mammalian proteasome is engaged to degrade a bulky fraction of soluble intracellular proteins both in an ubiquitin-dependent and independent manner. The proteasome is composed by a central catalytic core--the 20S proteasome--where three different proteases are located, whose activities can be measured. A detailed protocol for measuring accurately the three activities of the 20S proteasome in cell and tissue homogenates, using specific fluorogenic substrates and a microplate reader fluorometer, are described. Successful applications of this method include determining changes in the proteasomal activities during aging, anti-aging interventions, cell cycle analysis, and in various disease states including neurodegenerative diseases and cancers.
authors.forename: Cristovao F
authors.initials: CF
authors.lastname: Lima
authors.forename: Suresh I S
authors.initials: SI
authors.lastname: Rattan
mesh_terms: D000818:Animals; D057075:Enzyme Assays / Q000379:methods*; D006801:Humans; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*
chemical_list: D046988:Proteasome Endopeptidase Complex