Autor: |
Kessler, B, Michielin, O, Blanchard, C L, Apostolou, I, Delarbre, C, Gachelin, G, Grégoire, C, Malissen, B, Cerottini, J C, Wurm, F, Karplus, M, Luescher, I F |
Zdroj: |
Journal of Biological Chemistry; February 1999, Vol. 274 Issue: 6 p3622-31, 10p |
Abstrakt: |
To elucidate the structural basis of T cell recognition of hapten-modified antigenic peptides, we studied the interaction of the T1 T cell antigen receptor (TCR) with its ligand, the H-2Kd-bound Plasmodium berghei circumsporozoite peptide 252-260 (SYIPSAEKI) containing photoreactive 4-azidobenzoic acid (ABA) on P. berghei circumsporozoite Lys259. The photoaffinity-labeled TCR residue(s) were mapped as Tyr48 and/or Tyr50 of complementary determining region 2beta (CDR2beta). Other TCR-ligand contacts were identified by mutational analysis. Molecular modeling, based on crystallographic coordinates of closely related TCR and major histocompatibility complex I molecules, indicated that ABA binds strongly and specifically in a cavity between CDR3alpha and CDR2beta. We conclude that TCR expressing selective Vbeta and CDR3alpha sequences form a binding domain between CDR3alpha and CDR2beta that can accommodate nonpeptidic moieties conjugated at the C-terminal portion of peptides binding to major histocompatibility complex (MHC) encoded proteins. |
Databáze: |
Supplemental Index |
Externí odkaz: |
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