Investigation of the Role of Sug1p in the Function of the Yeast 26S Proteasome

North Carolina State University, Raleigh NC

Investigators

Abstract

9982599 Swaffield Proteasomes are large protein complexes found within all eukaryotic cells that degrade proteins targeted for removal. The proteasome is critically involved in all aspects of cellular metabolism and is essential for cell viability. Proteasomes are composed of a core particle and a regulatory particle that binds substrate proteins, unfolds them, and feeds them into the core particle for degradation. The unfolding of the substrate proteins requires energy supplied by ATP. The regulatory particle contains six highly similar ATPases central to the functioning of the proteasome. These ATPases are thought to form a ring at the interface of the core and regulatory particles. While the organization of the core particle has been determined by x-ray crystallography, the organization of the regulatory particle is still unknown. In these studies, working with the model eukaryote Saccharomyces cerevisiae (bakers yeast), a number of techniques will be used to determine the organization of the six ATPases within the regulatory particle. In addition ATPase/substrate interactions will be investigated and a series of novel mutations in one of the ATPases (Sug1p) isolated and characterized. These experiments will serve as a framework to probe the dynamic operation of an essential cellular component.