4I48

Structure of HLA-A68 complexed with an HIV Env derived peptide

Summary for 4I48

• Entry DOI: 10.2210/pdb4i48/pdb
• Related: 4HWZ 4HX1
• Descriptor: HLA class I histocompatibility antigen, A-68 alpha chain, Beta-2-microglobulin, 9-mer peptide from Envelope glycoprotein gp160, ... (4 entities in total)
• Functional Keywords: monomer, peptide presentation, immune system
• Biological source: Homo sapiens (human); More
• Cellular location: Membrane; Single-pass type I membrane protein: P01891; Secreted: P61769; Transmembrane protein gp41: Virion membrane; Single-pass type I membrane protein. Surface protein gp120: Virion membrane; Peripheral membrane protein: Q70626
• Total number of polymer chains: 3
• Total formula weight: 44451.29

Authors

Niu, L.,Cheng, H.,Zhang, S.,Tan, S.,Zhang, Y.,Qi, J.,Liu, J.,Gao, G.F. (deposition date: 2012-11-27, release date: 2013-10-02, Last modification date: 2024-10-30)

Primary citation

Niu, L.,Cheng, H.,Zhang, S.,Tan, S.,Zhang, Y.,Qi, J.,Liu, J.,Gao, G.F.
Structural basis for the differential classification of HLA-A*6802 and HLA-A*6801 into the A2 and A3 supertypes
Mol.Immunol., 55:381-392, 2013

PubMed Abstract: High polymorphism is one of the most important features of human leukocyte antigen (HLA) alleles, which were initially classified by serotyping but have recently been re-grouped into supertypes according to their peptide presentation properties. Two relatively prevalent HLA alleles HLA-A*6801 and HLA-A*6802, are classified into the same serotype HLA-A68. However, based on their distinct peptide-binding characteristics, HLA-A*6801 is grouped into A3 supertype, whereas HLA-A*6802 belongs to A2 supertype, similar to HLA-A*0201. Thusfar, the structural basis of the different supertype definitions of these serotyping-identical HLA alleles remains largely unknown. Herein, we determined the structures of HLA-A*6801 and HLA-A*6802 presenting three typical A3 and A2 supertype-restricted peptides, respectively. The binding capabilities of these peptides to HLA-A*6801, HLA-A*6802, and HLA-A*0201 were analyzed. These data indicate that the similar conformations of the residues within the F pocket contribute to close-related peptide binding features of HLA-A*6802 and HLA-A*0201. However, the overall structure and the peptide conformation of HLA-A*6802 are more similar to HLA-A*6801 rather than HLA-A*0201 which illuminates the similar serotype grouping of HLA-A*6802 and HLA-A*6801. Our findings are helpful for understanding the divergent peptide presentation and virus-specific CTL responses impacted by MHC micropolymorphisms and also elucidate the molecular basis of HLA supertype definitions.

PubMed: 23566939
DOI: 10.1016/j.molimm.2013.03.015

Experimental method

X-RAY DIFFRACTION (2.799 Å)