title: 26S and PA28-20S Proteasome Activity in Cytosolic Extracts from Embryonic Stem Cells.
abstract: The proteasome is a complex multisubunit protease that plays a major role in the degradation of proteins in eukaryotic cells. Proteasome function is one of the key players regulating the proteome and it is vital for many cellular processes. The method described here makes it possible to assay the proteolytic capacities of proteasome complexes separately in crude cytosolic extracts from ES cells. The method is based on hydrolysis of a fluorogenic peptide substrate in lysates prepared under conditions that favor the interactions of the 20S proteasomal catalytical core with either the 19S or the PA28αβ proteasome regulator.
authors.affiliation: Discovery Sciences, AstraZeneca R&D, SE-431 83, Mölndal, Sweden. malin.hernebring@astrazeneca.com.
authors.forename: Malin
authors.initials: M
authors.lastname: Hernebring
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D003600:Cytosol / Q000201:enzymology*; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000201:enzymology*; D057075:Enzyme Assays / Q000379:methods; D006801:Humans; D046988:Proteasome Endopeptidase Complex / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D046988:Proteasome Endopeptidase Complex
keywords: 19S proteasome activator; Cell differentiation; Embryonic stem cells; PA28 proteasome activator; Proteasome; Proteasome activity