title: Alanine scanning mutagenesis of an alphabeta T cell receptor: mapping the energy of antigen recognition.
abstract: The T cell receptor (TCR) from the alloreactive T lymphocyte 2C recognizes a nonamer peptide QL9 complexed with the MHC class I molecule H2-Ld. Forty-two single-site alanine substitutions of the 2C TCR were analyzed for binding to QL9/Ld and anti-TCR antibodies. The results provided a detailed energy map of T cell antigen recognition and indicated that the pMHC and clonotypic antibody epitopes on the TCR were similar. Although residues in each Valpha and Vbeta CDR are important in binding pMHC, the most significant energy for the TCR/QL9/Ld interaction was contributed by CDRs 1 and 2 of both alpha and beta chains. The extent to which the individual energy contributions are directed at class I helices or peptide was also assessed.
authors.affiliation: Department of Biochemistry, University of Illinois, Urbana 61801, USA.
authors.forename: T C
authors.initials: TC
authors.lastname: Manning
authors.forename: C J
authors.initials: CJ
authors.lastname: Schlueter
authors.forename: T C
authors.initials: TC
authors.lastname: Brodnicki
authors.forename: E A
authors.initials: EA
authors.lastname: Parke
authors.forename: J A
authors.initials: JA
authors.lastname: Speir
authors.forename: K C
authors.initials: KC
authors.lastname: Garcia
authors.forename: L
authors.initials: L
authors.lastname: Teyton
authors.forename: I A
authors.initials: IA
authors.lastname: Wilson
authors.forename: D M
authors.initials: DM
authors.lastname: Kranz
mesh_terms: D000409:Alanine / Q000737:chemistry; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D000906:Antibodies / Q000378:metabolism; D001665:Binding Sites; D000939:Epitopes; D006183:H-2 Antigens / Q000378:metabolism; D064532:Histocompatibility Antigen H-2D; D066298:In Vitro Techniques; D051379:Mice; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D017510:Protein Folding; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D013601:T-Lymphocytes / Q000276:immunology; D013816:Thermodynamics
chemical_list: D000906:Antibodies; D000939:Epitopes; D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D; D016693:Receptors, Antigen, T-Cell, alpha-beta; D000409:Alanine