Pba3-Pba4 heterodimer acts as a molecular matchmaker in proteasome α-ring formation.
Eukaryotic proteasome assembly is assisted by multiple dedicated chaperones. In yeast, formation of the heteroheptameric ring composed of α1-α7 subunits is promoted by the heterodimeric chaperone Pba3-Pba4. Here we reveal that in the absence of this dimeric chaperone, α2 replaces α4 during α-ring assembly, thereby giving rise to a non-productive ... complex that lacks α4, β1, β5, β6, and β7 subunits and aggregates of α4. Furthermore, our structure-guided mutational data demonstrate that the Pba3-Pba4 heterodimer acts as molecular matchmaker reinforcing the interaction between α4 and α5, which is the crucial step in the α-ring formation.
Mesh Terms:
Escherichia coli, Models, Molecular, Molecular Chaperones, Mutation, Proteasome Endopeptidase Complex, Protein Conformation, Protein Multimerization, Protein Subunits, Recombinant Fusion Proteins, Saccharomyces cerevisiae Proteins
Escherichia coli, Models, Molecular, Molecular Chaperones, Mutation, Proteasome Endopeptidase Complex, Protein Conformation, Protein Multimerization, Protein Subunits, Recombinant Fusion Proteins, Saccharomyces cerevisiae Proteins
Biochem. Biophys. Res. Commun.
Date: Jul. 25, 2014
PubMed ID: 24996173
View in: Pubmed Google Scholar
Download Curated Data For This Publication
187157
Switch View:
- Interactions 6