title: Structural basis of CD8 coreceptor function revealed by crystallographic analysis of a murine CD8alphaalpha ectodomain fragment in complex with H-2Kb.
abstract: The crystal structure of the two immunoglobulin variable-like domains of the murine CD8alphaalpha homodimer complexed to the class I MHC H-2Kb molecule at 2.8 A resolution shows that CD8alphaalpha binds to the protruding MHC alpha3 domain loop in an antibody-like manner. Comparison of mouse CD8alphaalpha/H-2Kb and human CD8alphaalpha/HLA-A2 complexes reveals shared as well as species-specific recognition features. In both species, coreceptor function apparently involves the participation of CD8 dimer in a bidentate attachment to an MHC class I molecule in conjunction with a T cell receptor without discernable conformational alteration of the peptide or MHC antigen-presenting platform.
authors.affiliation: Laboratory of Immunobiology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA.
authors.forename: P S
authors.initials: PS
authors.lastname: Kern
authors.forename: M K
authors.initials: MK
authors.lastname: Teng
authors.forename: A
authors.initials: A
authors.lastname: Smolyar
authors.forename: J H
authors.initials: JH
authors.lastname: Liu
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: R E
authors.initials: RE
authors.lastname: Hussey
authors.forename: R
authors.initials: R
authors.lastname: Spoerl
authors.forename: H C
authors.initials: HC
authors.lastname: Chang
authors.forename: E L
authors.initials: EL
authors.lastname: Reinherz
authors.forename: J H
authors.initials: JH
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016827:CD8 Antigens / Q000737:chemistry* / Q000235:genetics; D018360:Crystallography, X-Ray; D019281:Dimerization; D006183:H-2 Antigens / Q000737:chemistry* / Q000235:genetics; D015789:HLA-A2 Antigen / Q000737:chemistry / Q000235:genetics; D006801:Humans; D046911:Macromolecular Substances; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics
chemical_list: D016827:CD8 Antigens; D006183:H-2 Antigens; C032876:H-2Kb protein, mouse; D015789:HLA-A2 Antigen; D046911:Macromolecular Substances; D010446:Peptide Fragments; D011994:Recombinant Proteins