1INQ

Structure of Minor Histocompatibility Antigen peptide, H13a, complexed to H2-Db

Summary for 1INQ

• Entry DOI: 10.2210/pdb1inq/pdb
• Descriptor: H-2 CLASS I HISTOCOMPATIBILITY ANTIGEN, D-B ALPHA CHAIN, BETA-2 MICROGLOBULIN, MHC Class I H13a minor histocompatibility peptide, ... (5 entities in total)
• Functional Keywords: minor histocompatibility antigen, mhc complex, immune system
• Biological source: Mus musculus (house mouse); More
• Cellular location: Membrane; Single-pass type I membrane protein: P01899; Secreted: P01887; Endoplasmic reticulum membrane; Multi-pass membrane protein. Isoform 4: Cell membrane; Multi-pass membrane protein: Q9D8V0
• Total number of polymer chains: 3
• Total formula weight: 44782.24

Authors

Ostrov, D.A.,Roden, M.M.,Shi, W.,Palmieri, E.,Christianson, G.J.,Mendoza, L.,Villaflor, G.,Tilley, D.,Shastri, N.,Grey, H.,Almo, S.C.,Roopenian, D.,Nathenson, S.G. (deposition date: 2001-05-14, release date: 2002-03-20, Last modification date: 2024-11-13)

Primary citation

Ostrov, D.A.,Roden, M.M.,Shi, W.,Palmieri, E.,Christianson, G.J.,Mendoza, L.,Villaflor, G.,Tilley, D.,Shastri, N.,Grey, H.,Almo, S.C.,Roopenian, D.,Nathenson, S.G.
How H13 histocompatibility peptides differing by a single methyl group and lacking conventional MHC binding anchor motifs determine self-nonself discrimination.
J.Immunol., 168:283-289, 2002

PubMed Abstract: The mouse H13 minor histocompatibility (H) Ag, originally detected as a barrier to allograft transplants, is remarkable in that rejection is a consequence of an extremely subtle interchange, P4(Val/Ile), in a nonamer H2-D(b)-bound peptide. Moreover, H13 peptides lack the canonical P5(Asn) central anchor residue normally considered important for forming a peptide/MHC complex. To understand how these noncanonical peptide pMHC complexes form physiologically active TCR ligands, crystal structures of allelic H13 pD(b) complexes and a P5(Asn) anchored pD(b) analog were solved to high resolution. The structures show that the basis of TCRs to distinguish self from nonself H13 peptides is their ability to distinguish a single solvent-exposed methyl group. In addition, the structures demonstrate that there is no need for H13 peptides to derive any stabilization from interactions within the central C pocket to generate fully functional pMHC complexes. These results provide a structural explanation for a classical non-MHC-encoded H Ag, and they call into question the requirement for contact between anchor residues and the major MHC binding pockets in vaccine design.

PubMed: 11751972

Experimental method

X-RAY DIFFRACTION (2.2 Å)