Isolation of the Schizosaccharomyces pombe proteasome subunit Rpn7 and a structure-function study of the proteasome-COP9-initiation factor domain.

ABSTRACT: Proper assembly of the 26 S proteasome is required to efficiently degrade polyubiquitinated proteins. Many proteasome subunits contain the proteasome-COP9-initiation factor (PCI) domain, thus raising the possibility that the PCI domain may play a role in mediating proteasome assembly. We have previously characterized the PCI protein Yin6, a fission yeast ortholog of the mammalian Int6 that has been implicated in breast oncogenesis, and demonstrated that it binds and regulates the assembly of the proteasome. In this study, we isolated another PCI proteasome subunit, Rpn7, as a high copy suppressor that rescued the proteasome defects in yin6 null cells. To better define the function of the PCI domain, we aligned protein sequences to identify a conserved leucine residue that is present in nea

SUBMITTER: Sha Z 

PROVIDER: S-EPMC3012426 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature