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2fny
From Proteopedia
Homobelactosin C bound to the yeast 20S proteasome
Overview
Most class I MHC ligands are generated from the vast majority of cellular proteins by proteolysis within the ubiquitin-proteasome pathway and are presented on the cell surface by MHC class I molecules. Here, we present the crystallographic analysis of yeast 20S proteasome in complex with the inhibitor homobelactosin C. The structure reveals a unique inhibitor-binding mode and provides information about the composition of proteasomal primed substrate-binding sites. IFN-gamma inducible substitution of proteasomal constitutive subunits by immunosubunits modulates characteristics of generated peptides, thus producing fragments with higher preference for binding to MHC class I molecules. The structural data for the proteasome:homobelactosin C complex provide an explanation for involvement of immunosubunits in antigen generation and open perspectives for rational design of ligands, inhibiting exclusively constitutive proteasomes or immunoproteasomes.
About this Structure
2FNY is a Protein complex structure of sequences from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Inhibitor-binding mode of homobelactosin C to proteasomes: new insights into class I MHC ligand generation., Groll M, Larionov OV, Huber R, de Meijere A, Proc Natl Acad Sci U S A. 2006 Mar 21;103(12):4576-9. Epub 2006 Mar 13. PMID:16537370 Page seeded by OCA on Sun May 4 04:07:01 2008
