1QO3

Complex between NK cell receptor Ly49A and its MHC class I ligand H-2Dd

Summary for 1QO3

• Entry DOI: 10.2210/pdb1qo3/pdb
• Descriptor: MHC CLASS I H-2DD HEAVY CHAIN, BETA-2-MICROGLOBULIN, LY49A, ... (6 entities in total)
• Functional Keywords: receptor/immune system, complex (nk receptor-mhc class i), nk cell, inhibitory receptor, mhc-i, c-type lectin-like, histocompatibility, b2m, ly49, ly-49, receptor-immune system complex
• Biological source: MUS MUSCULUS (MOUSE); More
• Cellular location: Membrane; Single-pass type I membrane protein: P01900; Secreted: 1QO3; Transmembrane protein gp41: Virion membrane; Single-pass type I membrane protein. Surface protein gp120: Virion membrane; Peripheral membrane protein: P01887; Membrane; Single-pass type II membrane protein: P04582
• Total number of polymer chains: 5
• Total formula weight: 77161.57

Authors

Tormo, J.,Mariuzza, R.A. (deposition date: 1999-11-01, release date: 2000-01-02, Last modification date: 2023-12-13)

Primary citation

Tormo, J.,Natarajan, K.,Margulies, D.H.,Mariuzza, R.A.
Crystal Structure of a Lectin-Like Natural Killer Cell Receptor Bound to its Mhc Class I Ligand
Nature, 402:623-, 1999

PubMed Abstract: Natural killer (NK) cell function is regulated by NK receptors that interact with MHC class I (MHC-I) molecules on target cells. The murine NK receptor Ly49A inhibits NK cell activity by interacting with H-2D(d) through its C-type-lectin-like NK receptor domain. Here we report the crystal structure of the complex between the Ly49A NK receptor domain and unglycosylated H-2D(d). The Ly49A dimer interacts extensively with two H-2D(d) molecules at distinct sites. At one interface, a single Ly49A subunit contacts one side of the MHC-I peptide-binding platform, presenting an open cavity towards the conserved glycosylation site on the H-2D(d) alpha2 domain. At a second, larger interface, the Ly49A dimer binds in a region overlapping the CD8-binding site. The smaller interface probably represents the interaction between Ly49A on the NK cell and MHC-I on the target cell, whereas the larger one suggests an interaction between Ly49A and MHC-I on the NK cell itself. Both Ly49A binding sites on MHC-I are spatially distinct from that of the T-cell receptor.

PubMed: 10604468
DOI: 10.1038/45170

Experimental method

X-RAY DIFFRACTION (2.3 Å)