{"display":true,"structure":{"allele":{"alpha":{"identifier":"ipd-imgt:HLA35266","locus":"hla-a","match_type":"histo:exact","name":"HLA-A*02:01","slug":"hla_a_02_01","species_stem":"hla"},"beta":{}},"assemblies":{"1":{"assembly_name":"4pjh_1","chains":["A","B","E","F"],"downloaded_at":"2022-11-09T14:35:20.498031"}},"assembly_count":null,"assigned_chains":{"beta2m":{"chains":["B","D"],"match_type":"histo:assign_chains","score":0.99,"sequence":"MIQRTPKIQVYSRHPAENGKSNFLNCYVSGFHPSDIEVDLLKNGERIEKVEHSDLSFSKDWSFYLLYYTEFTPTEKDEYACRVNHVTLSQPKIVKWDRDM"},"mr1":{"chains":["A","C"],"match_type":"histo:assign_chains","score":1.0,"sequence":"MRTHSLRYFRLGVSDPIHGVPEFISVGYVDSHPITTYDSVTRQKEPRAPWMAENLAPDHWERYTQLLRGWQQMFKVELKRLQRHYNHSGSHTYQRMIGCELLEDGSTTGFLQYAYDGQDFLIFNKDTLSWLAVDNVAHTIKQAWEANQHELLYQKNWLEEECIAWLKRFLEYGKDTLQRTEPPLVRVNRKETFPGVTALFCKAHGFYPPEIYMTWMKNGEEIVQEIDYGDILPSGDGTYQAWASIELDPQSSNLYSCHVEHSGVHMVLQVP"},"tcr_alpha":{"chains":["E"],"match_type":"stcrdab","sequence":"HMGQNIDQPTEMTATEGAIVQINCTYQTSGFNGLFWYQQHAGEAPTFLSYNVLDGLEEKGRFSSFLSRSKGYSYLLLKELQMKDSASYLCAAMDSNYQLIWGAGTKLIIKPDIQNPDPAVYQLRDSKSSDKSVCLFTDFDSQTNVSQSKDSDVYITDKCVLDMRSMDFKSNSAVAWSNKSDFACANAFNNSIIPEDTFFPSPESS","subgroup":"TRAV1"},"tcr_beta":{"chains":["F"],"match_type":"stcrdab","sequence":"HMNAGVTQTPKFQVLKTGQSMTLQCAQDMNHNSMYWYRQDPGMGLRLIYYSASEGTTDKGEVPNGYNVSRLNKREFSLRLESAAPSQTSVYFCASSGGDSGELFFGEGSRLTVLEDLKNVFPPEVAVFEPSEAEISHTQKATLVCLATGFYPDHVELSWWVNGKEVHSGVCTDPQPLKEQPALNDSRYALSSRLRVSATFWQNPRNHFRCQVQFYGLSENDEWTQDRAKPVTQIVSAEAWGRAD","subgroup":"TRBV6"}},"chronology":{"deposition_date":"2014-05-12","deposition_year":2014,"release_date":"2014-07-02","release_year":2014,"revision_date":"2014-10-01","revision_year":2014},"class":"class_i","classical":false,"complex_type":"mr1_with_alpha_beta_tcr","components":["mr1","beta2m","tcr_alpha","tcr_beta"],"experimental_method":"X-ray diffraction","facets":{},"ligands":[],"locus":"hla-a","manually_edited":{},"missing_residues":[],"page_title":"4PJH | Non-classical MHC Class I molecule MR1 with Alpha/Beta T cell receptor","pdb_code":"4pjh","pdb_title":"Structure of human MR1-ac-6-fp in complex with human MAIT b-g8 TCR","peptide":{"actual_sequence":null,"epitope_info":{},"features":[],"full_sequence":null,"gap_info":{},"gapped_sequence":null,"length":{"numeric":null,"text":null},"unnatural_amino_acids":[]},"publication":{"abstract":"Mucosal-associated invariant T (MAIT) cells express an invariant T cell receptor (TCR) \u03b1-chain (TRAV1-2 joined to TRAJ33, TRAJ20, or TRAJ12 in humans), which pairs with an array of TCR \u03b2-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) 3\u03b2 loop. Analysis of seven TRBV6-1(+) MAIT TCRs demonstrated how CDR3\u03b2 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.","bibjson":{"author":[{"initials":"SB","lastname":"Eckle","name":"Eckle SB"},{"initials":"RW","lastname":"Birkinshaw","name":"Birkinshaw RW"},{"initials":"L","lastname":"Kostenko","name":"Kostenko L"},{"initials":"AJ","lastname":"Corbett","name":"Corbett AJ"},{"initials":"HE","lastname":"McWilliam","name":"McWilliam HE"},{"initials":"R","lastname":"Reantragoon","name":"Reantragoon R"},{"initials":"Z","lastname":"Chen","name":"Chen Z"},{"initials":"NA","lastname":"Gherardin","name":"Gherardin NA"},{"initials":"T","lastname":"Beddoe","name":"Beddoe T"},{"initials":"L","lastname":"Liu","name":"Liu L"},{"initials":"O","lastname":"Patel","name":"Patel O"},{"initials":"B","lastname":"Meehan","name":"Meehan B"},{"initials":"DP","lastname":"Fairlie","name":"Fairlie DP"},{"initials":"JA","lastname":"Villadangos","name":"Villadangos JA"},{"initials":"DI","lastname":"Godfrey","name":"Godfrey DI"},{"initials":"L","lastname":"Kjer-Nielsen","name":"Kjer-Nielsen L"},{"initials":"J","lastname":"McCluskey","name":"McCluskey J"},{"initials":"J","lastname":"Rossjohn","name":"Rossjohn J"}],"identifier":[{"id":"10.1084/jem.20140484","type":"doi"},{"id":"25049336","type":"pubmed"}],"issue":["8"],"journal":{"iso_abbreviation":"J. Exp. Med.","name":""},"pages":["1585-600"],"title":"A molecular basis underpinning the T cell receptor heterogeneity of mucosal-associated invariant T cells.","type":"article","url":"https://rupress.org/jem/article/211/8/1585/41722/A-molecular-basis-underpinning-the-T-cell-receptor","volume":["211"],"year":[2014]},"in_pmc":"N","in_pmce":"Y","open_access":"Y"},"resolution":"2.00","same_as":{"pdbe":{"url":"https://www.ebi.ac.uk/pdbe/entry/pdb/4pjh"},"rcsb":{"url":"https://www.rcsb.org/structure/4pjh"},"stcrdab":{"url":"http://opig.stats.ox.ac.uk/webapps/stcrdab/StrViewer?pdb=4pjh"}},"species":{"common_name":"Human","match_type":"histo:assign_species","scientific_name":"Homo sapiens","slug":"homo_sapiens"},"tcr":{"alpha":{"chains":["E"],"subgroup":"TRAV1"},"beta":{"chains":["F"],"subgroup":"TRBV6"},"pdb_code":"4pjh"},"title":"Non-classical MHC Class I molecule MR1 with Alpha/Beta T cell receptor at 2.00Å resolution","unique_chain_count":4}}