 |
PDBsum entry 3e3q
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Immune system
|
PDB id
|
|
|
|
3e3q
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
(+ 2 more)
175 a.a.
|
|
|
|
|
|
|
|
|
|
|
(+ 2 more)
109 a.a.
|
|
|
|
|
|
|
|
|
|
|
(+ 2 more)
111 a.a.
|
|
|
|
|
|
|
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Distinct cdr3 conformations in tcrs determine the level of cross-Reactivity for diverse antigens, But not the docking orientation.
|
|
|
Authors
|
|
L.L.Jones,
L.A.Colf,
J.D.Stone,
K.C.Garcia,
D.M.Kranz.
|
|
|
Ref.
|
|
J Immunol, 2008,
181,
6255-6264.
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
T cells are known to cross-react with diverse peptide MHC Ags through their
alphabeta TCR. To explore the basis of such cross-reactivity, we examined the 2C
TCR that recognizes two structurally distinct ligands, SIY-K(b) and alloantigen
QL9-L(d). In this study we characterized the cross-reactivity of several
high-affinity 2C TCR variants that contained mutations only in the CDR3alpha
loop. Two of the TCR lost their ability to cross-react with the reciprocal
ligand (SIY-K(b)), whereas another TCR (m67) maintained reactivity with both
ligands. Crystal structures of four of the TCRs in complex with QL9-L(d) showed
that CDR1, CDR2, and CDR3beta conformations and docking orientations were
remarkably similar. Although the CDR3alpha loop of TCR m67 conferred a 2000-fold
higher affinity for SIY-K(b), the TCR maintained the same docking angle on
QL9-L(d) as the 2C TCR. Thus, CDR3alpha dictated the affinity and level of
cross-reactivity, yet it did so without affecting the conserved docking
orientation.
|
|
|
|
|
|
|
