4GUP

Structure of MHC-class I related molecule MR1


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.2 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.193 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

MR1 presents microbial vitamin B metabolites to MAIT cells

Kjer-Nielsen, L.Patel, O.Corbett, A.J.Le Nours, J.Meehan, B.Liu, L.Bhati, M.Chen, Z.Kostenko, L.Reantragoon, R.Williamson, N.A.Purcell, A.W.Dudek, N.L.McConville, M.J.O'Hair, R.A.J.Khairallah, G.N.Godfrey, D.I.Fairlie, D.P.Rossjohn, J.McCluskey, J.

(2012) Nature 491: 717-723

  • DOI: 10.1038/nature11605

  • PubMed Abstract: 
  • Antigen-presenting molecules, encoded by the major histocompatibility complex (MHC) and CD1 family, bind peptide- and lipid-based antigens, respectively, for recognition by T cells. Mucosal-associated invariant T (MAIT) cells are an abundant populati ...

    Antigen-presenting molecules, encoded by the major histocompatibility complex (MHC) and CD1 family, bind peptide- and lipid-based antigens, respectively, for recognition by T cells. Mucosal-associated invariant T (MAIT) cells are an abundant population of innate-like T cells in humans that are activated by an antigen(s) bound to the MHC class I-like molecule MR1. Although the identity of MR1-restricted antigen(s) is unknown, it is present in numerous bacteria and yeast. Here we show that the structure and chemistry within the antigen-binding cleft of MR1 is distinct from the MHC and CD1 families. MR1 is ideally suited to bind ligands originating from vitamin metabolites. The structure of MR1 in complex with 6-formyl pterin, a folic acid (vitamin B9) metabolite, shows the pterin ring sequestered within MR1. Furthermore, we characterize related MR1-restricted vitamin derivatives, originating from the bacterial riboflavin (vitamin B2) biosynthetic pathway, which specifically and potently activate MAIT cells. Accordingly, we show that metabolites of vitamin B represent a class of antigen that are presented by MR1 for MAIT-cell immunosurveillance. As many vitamin biosynthetic pathways are unique to bacteria and yeast, our data suggest that MAIT cells use these metabolites to detect microbial infection.


    Organizational Affiliation

    Department of Microbiology & Immunology, University of Melbourne, Parkville, Victoria 3010, Australia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Major histocompatibility complex class I-related gene protein
A, C
271Homo sapiensGene Names: MR1
Find proteins for Q95460 (Homo sapiens)
Go to Gene View: MR1
Go to UniProtKB:  Q95460
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Beta-2-microglobulin
B, D
99Homo sapiensGene Names: B2M
Find proteins for P61769 (Homo sapiens)
Go to Gene View: B2M
Go to UniProtKB:  P61769
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
6FP
Query on 6FP

Download SDF File 
Download CCD File 
A, C
2-amino-4-oxo-3,4-dihydropteridine-6-carbaldehyde
6-formylpterin
C7 H5 N5 O2
LLJAQDVNMGLRBD-UHFFFAOYSA-N
 Ligand Interaction
CL
Query on CL

Download SDF File 
Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.2 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.193 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 59.154α = 90.00
b = 89.777β = 90.00
c = 171.338γ = 90.00
Software Package:
Software NamePurpose
BUSTERrefinement
MOSFLMdata reduction
SCALAdata scaling
Blu-Icedata collection
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-10-17
    Type: Initial release
  • Version 1.1: 2012-10-24
    Type: Database references
  • Version 1.2: 2012-12-05
    Type: Database references