Solution mapping of T cell receptor docking footprints on peptide-MHC.
T cell receptor (TCR) recognition of peptide-MHC (pMHC) is central to the cellular immune response. A large database of TCR-pMHC structures is needed to reveal general structural principles, such as whether the repertoire of TCR/MHC docking modes is dictated by a "recognition code" between conserved elements of the TCR and MHC genes. Although approximately 17 cocrystal structures of unique TCR-pMHC complexes have been determined, cocrystallization of soluble TCR and pMHC remains a major technical obstacle in the field. Here we demonstrate a strategy, based on NMR chemical shift mapping, that permits rapid and reliable analysis of the solution footprint made by a TCR when binding onto the pMHC surface. We mapped the 2C TCR binding interaction with its allogeneic ligand H-2Ld-QL9 and identified a group of NMR-shifted residues that delineated a clear surface of the MHC that we defined as the TCR footprint. We subsequently found that the docking footprint described by NMR shifts was highly accurate compared with a recently determined high-resolution crystal structure of the same complex. The same NMR footprint analysis was done on a high-affinity mutant of the TCR. The current work serves as a foundation to explore the molecular dynamics of pMHC complexes and to rapidly determine the footprints of many Ld-specific TCRs.
Varani
Luca
L
Howard Hughes Medical Institute, Department of Molecular and Cellular Physiology, and Stanford Magnetic Resonance Laboratory, Stanford University School of Medicine, Beckman B171B, 279 Campus Drive, Stanford, CA 94305, USA.
Bankovich
Alexander J
AJ
Liu
Corey W
CW
Colf
Leremy A
LA
Jones
Lindsay L
LL
Kranz
David M
DM
Puglisi
Joseph D
JD
Garcia
K Christopher
KC
D000595:Amino Acid Sequence; D000818:Animals; D022801:Complementarity Determining Regions; D006183:H-2 Antigens / Q000737:chemistry*; D064532:Histocompatibility Antigen H-2D; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008969:Molecular Sequence Data; D017510:Protein Folding; D011948:Receptors, Antigen, T-Cell / Q000737:chemistry*
D022801:Complementarity Determining Regions; D006183:H-2 Antigens; C032876:H-2Kb protein, mouse; D064532:Histocompatibility Antigen H-2D; D011948:Receptors, Antigen, T-Cell