3PGC

Crystal Structure of HLA-DR1 with CLIP106-120, flipped peptide orientation

Summary for 3PGC

• Entry DOI: 10.2210/pdb3pgc/pdb
• Related: 3PDO 3PGD
• Descriptor: HLA class II histocompatibility antigen, DR alpha chain, HLA class II histocompatibility antigen, DRB1-1 beta chain, HLA class II histocompatibility antigen gamma chain, ... (6 entities in total)
• Functional Keywords: mhc class ii, mhc ii, immune system, self antigen, invariant chain, clip
• Biological source: Homo sapiens (human); More
• Cellular location: Cell membrane; Single-pass type I membrane protein: P01903 P04229; Cell membrane; Single-pass type II membrane protein (Potential): P04233
• Total number of polymer chains: 6
• Total formula weight: 94548.77

Authors

Gunther, S.,Schlundt, A.,Sticht, J.,Roske, Y.,Heinemann, U.,Wiesmuller, K.-H.,Jung, G.,Falk, K.,Rotzschke, O.,Freund, C. (deposition date: 2010-11-01, release date: 2010-12-08, Last modification date: 2024-11-27)

Primary citation

Gunther, S.,Schlundt, A.,Sticht, J.,Roske, Y.,Heinemann, U.,Wiesmuller, K.H.,Jung, G.,Falk, K.,Rotzschke, O.,Freund, C.
Bidirectional binding of invariant chain peptides to an MHC class II molecule.
Proc.Natl.Acad.Sci.USA, 107:22219-22224, 2010

PubMed Abstract: T-cell recognition of peptides bound to MHC class II (MHCII) molecules is a central event in cell-mediated adaptive immunity. The current paradigm holds that prebound class II-associated invariant chain peptides (CLIP) and all subsequent antigens maintain a canonical orientation in the MHCII binding groove. Here we provide evidence for MHCII-bound CLIP inversion. NMR spectroscopy demonstrates that the interconversion from the canonical to the inverse alignment is a dynamic process, and X-ray crystallography shows that conserved MHC residues form a hydrogen bond network with the peptide backbone in both orientations. The natural catalyst HLA-DM accelerates peptide reorientation and the exchange of either canonically or inversely bound CLIP against antigenic peptide. Thus, noncanonical MHC-CLIP displays the hallmarks of a structurally and functionally intact antigen-presenting complex.

PubMed: 21115828
DOI: 10.1073/pnas.1014708107

Experimental method

X-RAY DIFFRACTION (2.66 Å)