7TUF

Crystal structure of Tapasin in complex with PaSta1-Fab

Summary for 7TUF

• Entry DOI: 10.2210/pdb7tuf/pdb
• Related: 7TUC 7TUD 7TUE 7TUG 7TUH
• Descriptor: Tapasin, PaSta1 Fab heavy chain, PaSta1 Fab kappa light chain, ... (5 entities in total)
• Functional Keywords: pasta, fab, antibody, igg, mhc-i, hla, peptide loading complex, plc, antigen presentation, immune response, immune system
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 6
• Total formula weight: 187453.92

Authors

Jiang, J.,Natarajan, K.,Taylor, D.K.,Boyd, L.F.,Margulies, D.H. (deposition date: 2022-02-02, release date: 2022-09-07, Last modification date: 2024-10-30)

Primary citation

Jiang, J.,Taylor, D.K.,Kim, E.J.,Boyd, L.F.,Ahmad, J.,Mage, M.G.,Truong, H.V.,Woodward, C.H.,Sgourakis, N.G.,Cresswell, P.,Margulies, D.H.,Natarajan, K.
Structural mechanism of tapasin-mediated MHC-I peptide loading in antigen presentation.
Nat Commun, 13:5470-5470, 2022

PubMed Abstract: Loading of MHC-I molecules with peptide by the catalytic chaperone tapasin in the peptide loading complex plays a critical role in antigen presentation and immune recognition. Mechanistic insight has been hampered by the lack of detailed structural information concerning tapasin-MHC-I. We present here crystal structures of human tapasin complexed with the MHC-I molecule HLA-B*44:05, and with each of two anti-tapasin antibodies. The tapasin-stabilized peptide-receptive state of HLA-B*44:05 is characterized by distortion of the peptide binding groove and destabilization of the β-microglobulin interaction, leading to release of peptide. Movements of the membrane proximal Ig-like domains of tapasin, HLA-B*44:05, and β-microglobulin accompany the transition to a peptide-receptive state. Together this ensemble of crystal structures provides insights into a distinct mechanism of tapasin-mediated peptide exchange.

PubMed: 36115831
DOI: 10.1038/s41467-022-33153-8

Experimental method

X-RAY DIFFRACTION (2.8 Å)