REGULATION OF PROTEASOME STRUCTURE AND FUNCTION

Proteasomes are cylindrical particles made up of a stack of four hepta meric rings. In animal cells the outer rings are made up of 7 differen t types of alpha subunits and the inner rings are composed of 7 out of 10 possible different beta subunits. Regulatory complexes can bind to the ends of the cylinder. We have investigated aspects of the assembl y, activity and subunit composition of core proteasome particles and 2 6S proteasomes, the localization of proteasome subpopulations, and the possible role of phosphorylation in determining proteasome localizati on, activities and association with regulatory components.