4PJ5

Structure of human MR1-Ac-6-FP in complex with human MAIT TRBV6-1 TCR


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.180 
  • R-Value Observed: 0.182 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

A molecular basis underpinning the T cell receptor heterogeneity of mucosal-associated invariant T cells.

Eckle, S.B.Birkinshaw, R.W.Kostenko, L.Corbett, A.J.McWilliam, H.E.Reantragoon, R.Chen, Z.Gherardin, N.A.Beddoe, T.Liu, L.Patel, O.Meehan, B.Fairlie, D.P.Villadangos, J.A.Godfrey, D.I.Kjer-Nielsen, L.McCluskey, J.Rossjohn, J.

(2014) J Exp Med 211: 1585-1600

  • DOI: 10.1084/jem.20140484
  • Primary Citation of Related Structures:  
    4PJF, 4PJG, 4PJH, 4PJI, 4PJA, 4PJB, 4PJC, 4PJD, 4PJE, 4PJ7

  • PubMed 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 metabol ...

    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.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800, Australia ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK lkn@unimelb.edu.au jamesm1@unimelb.edu.au jamie.rossjohn@monash.edu.



Macromolecules
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Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Major histocompatibility complex class I-related gene proteinAC271Homo sapiensMutation(s): 1 
Gene Names: MR1
Find proteins for Q95460 (Homo sapiens)
Explore Q95460 
Go to UniProtKB:  Q95460
NIH Common Fund Data Resources
PHAROS  Q95460
Protein Feature View
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  • Reference Sequence
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Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Beta-2-microglobulinBF100Homo sapiensMutation(s): 0 
Gene Names: B2MCDABP0092HDCMA22P
Find proteins for P61769 (Homo sapiens)
Explore P61769 
Go to UniProtKB:  P61769
NIH Common Fund Data Resources
PHAROS  P61769
Protein Feature View
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  • Reference Sequence
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Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
TCR-alphaDG203Homo sapiensMutation(s): 0 
Protein Feature View
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  • Reference Sequence
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Entity ID: 4
MoleculeChainsSequence LengthOrganismDetailsImage
TCR-betaEH245Homo sapiensMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
30W
Query on 30W

Download CCD File 
A, C
N-(6-formyl-4-oxo-3,4-dihydropteridin-2-yl)acetamide
C9 H7 N5 O3
DDBCPKAHJKOGKK-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.180 
  • R-Value Observed: 0.182 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 216.676α = 90
b = 69.872β = 104.14
c = 142.806γ = 90
Software Package:
Software NamePurpose
BUSTERrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-07-02
    Type: Initial release
  • Version 1.1: 2014-08-06
    Changes: Database references
  • Version 1.2: 2014-10-01
    Changes: Database references