spacer
spacer

PDBsum entry 4pjh

Go to PDB code: 
Top Page protein ligands metals Protein-protein interface(s) links
Immune system PDB id
4pjh
Contents
Protein chains
262 a.a.
99 a.a.
192 a.a.
239 a.a.
Ligands
GOL ×4
30W ×2
Metals
_NA ×4
Waters ×1541

References listed in PDB file
Key reference
Title A molecular basis underpinning the t cell receptor heterogeneity of mucosal-Associated invariant t cells.
Authors S.B.Eckle, R.W.Birkinshaw, L.Kostenko, A.J.Corbett, H.E.Mcwilliam, R.Reantragoon, Z.Chen, N.A.Gherardin, T.Beddoe, L.Liu, O.Patel, B.Meehan, D.P.Fairlie, J.A.Villadangos, D.I.Godfrey, L.Kjer-Nielsen, J.Mccluskey, J.Rossjohn.
Ref. J Exp Med, 2014, 211, 1585-1600. [DOI no: 10.1084/jem.20140484]
PubMed id 25049336
Abstract
Mucosal-associated invariant T (MAIT) cells express an invariant T cell receptor (TCR) α-chain (TRAV1-2 joined to TRAJ33, TRAJ20, or TRAJ12 in humans), which pairs with an array of TCR β-chains. MAIT TCRs can bind folate- and riboflavin-based metabolites restricted by the major histocompatibility complex (MHC)-related class I-like molecule, MR1. However, the impact of MAIT TCR and MR1-ligand heterogeneity on MAIT cell biology is unclear. We show how a previously uncharacterized MR1 ligand, acetyl-6-formylpterin (Ac-6-FP), markedly stabilized MR1, potently up-regulated MR1 cell surface expression, and inhibited MAIT cell activation. These enhanced properties of Ac-6-FP were attributable to structural alterations in MR1 that subsequently affected MAIT TCR recognition via conformational changes within the complementarity-determining region (CDR) 3β loop. Analysis of seven TRBV6-1(+) MAIT TCRs demonstrated how CDR3β hypervariability impacted on MAIT TCR recognition by altering TCR flexibility and contacts with MR1 and the Ag itself. Ternary structures of TRBV6-1, TRBV6-4, and TRBV20(+) MAIT TCRs in complex with MR1 bound to a potent riboflavin-based antigen (Ag) showed how variations in TRBV gene usage exclusively impacted on MR1 contacts within a consensus MAIT TCR-MR1 footprint. Moreover, differential TRAJ gene usage was readily accommodated within a conserved MAIT TCR-MR1-Ag docking mode. Collectively, MAIT TCR heterogeneity can fine-tune MR1 recognition in an Ag-dependent manner, thereby modulating MAIT cell recognition.
PROCHECK
Go to PROCHECK summary
 Headers

 

spacer

spacer