Endoplasmic reticulum chaperones stabilize ligand-receptive MR1 molecules for efficient presentation of metabolite antigens

Hamish EG McWilliam; Jeffrey YW Mak; Wael Awad; Matthew Zorkau; Sebastian Cruz-Gomez; Hui Jing Lim; Yuting Yan; Sam Wormald; Laura F Dagley; Sidonia BG Eckle; Alexandra J Corbett; Haiyin Liu; Shihan Li; Scott JJ Reddiex; Justine D Mintern; Ligong Liu; James McCluskey; Jamie Rossjohn; David P Fairlie; Jose A Villadangos

Journal article

Endoplasmic reticulum chaperones stabilize ligand-receptive MR1 molecules for efficient presentation of metabolite antigens

Hamish EG McWilliam, Jeffrey YW Mak, Wael Awad, Matthew Zorkau, Sebastian Cruz-Gomez, Hui Jing Lim, Yuting Yan, Sam Wormald, Laura F Dagley, Sidonia BG Eckle, Alexandra J Corbett, Haiyin Liu, Shihan Li, Scott JJ Reddiex, Justine D Mintern, Ligong Liu, James McCluskey, Jamie Rossjohn, David P Fairlie, Jose A Villadangos

Proceedings of the National Academy of Sciences of USA | NATL ACAD SCIENCES | Published : 2020

DOI: 10.1073/pnas.2011260117

Abstract

The antigen-presenting molecule MR1 (MHC class I-related protein 1) presents metabolite antigens derived from microbial vitamin B2 synthesis to activate mucosal-associated invariant T (MAIT) cells. Key aspects of this evolutionarily conserved pathway remain uncharacterized, including where MR1 acquires ligands and what accessory proteins assist ligand binding. We answer these questions by using a fluorophore-labeled stable MR1 antigen analog, a conformation-specific MR1 mAb, proteomic analysis, and a genome-wide CRISPR/Cas9 library screen. We show that the endoplasmic reticulum (ER) contains a pool of two unliganded MR1 conformers stabilized via interactions with chaperones tapasin and tapas..

View full abstract

University of Melbourne Researchers

Alexandra Corbett Author Microbiology and Immunology

Hamish McWilliam Author Microbiology and Immunology

Laura Dagley Author Medical Biology (W.E.H.I.)

Haiyin Liu Author Biochemistry and Pharmacology

James McCluskey Author

Related Projects (5)

DENDRITIC CELLS AND ANTIGEN PRESENTATION

José Villadangos studies the cells and molecules involved in Antigen Presentation. This phenomenon consists of the detection, capture and di..

ANTIGEN PRESENTATION, RECOGNITION AND THE IMMUNE RESPONSE

This program focuses on understanding the development of immunity during infection or inflammatory diseases using a broad array of technique..

Understanding recognition of vitamin B-based antigens by the immune system

This project aims to evaluate the range of molecules that can stimulate vitamin B-reactive T cells in mammals and amphibians, and the degree..

Understanding the biology of a novel immune cell type

This project aims to study immune cells that target harmful microbes by recognising by-products of their metabolism, and develop methods mod..

Defining a novel mechanism of pathogen detection conserved in mammals

This project aims to study the role of a host molecule in immune protection. Multicellular organisms need to recognise pathogens to initiate..

Grants

Awarded by Australian Research Council (ARC)

Awarded by ARC

Awarded by National Health and Medical Research Council

Awarded by ARC Centre of Excellence in Advanced Molecular Imaging Grant

Funding Acknowledgements

We thank Dr. Louise Boyle (University of Cambridge) for the kind gift of the plasmids for TAPBPR expression and PeTe4 mAb; Prof. Peter Cresswell for the kind gift of the 148.3 and PaSta1 mAbs; and the Antibody Services Facility and Genomics Hub (Walter and Eliza Hall Institute) and the Melbourne Cytometry Platform from the Doherty Institute node and the Biological Optical Microscopy Platform (University of Melbourne) for expert assistance. H.E.G.M. is supported by an Australian Research Council (ARC) Discovery Early Career Researcher Award (DE170100575), a University of Melbourne Early Career Researcher Grant, and the AMP Tomorrow Fund; A.J.C. is supported by an ARC Future Fellowship (FT160100083); S.B.G.E. is supported by an ARC Discovery Early Career Researcher Award (DE170100407); J.R. is supported by an ARC Australian Laureate Fellowship; D.P.F. and J.A.V. are supported by National Health and Medical Research Council Research Fellowships (1117017, 1058193). This research was supported by a National Health and Medical Research Council Program Grant (1113293), an ARC Discovery Grant (170102471), and an ARC Centre of Excellence in Advanced Molecular Imaging Grant (CE140100011).