7CIR

Peptide phosphorylation modification of MHC class I molecules

Summary for 7CIR

• Entry DOI: 10.2210/pdb7cir/pdb
• Descriptor: MHC class I antigen, Beta-2-microglobulin, ARG-ARG-PHE-SEP-ARG-SER-PRO-ILE-ARG-ARG, ... (4 entities in total)
• Functional Keywords: mhc i complex, p4-son3, immune system
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 3
• Total formula weight: 45223.08

Authors

Sun, M.W.,Feng, L.,Qi, J.X.,Liu, W.J.,Gao, G.F. (deposition date: 2020-07-08, release date: 2022-03-09, Last modification date: 2024-10-23)

Primary citation

Zhao, Y.,Sun, M.,Zhang, N.,Liu, X.,Yue, C.,Feng, L.,Ji, S.,Liu, X.,Qi, J.,Wong, C.C.L.,Gao, G.F.,Liu, W.J.
Phosphosite-dependent presentation of dual phosphorylated peptides by MHC class I molecules.
Iscience, 25:104013-104013, 2022

PubMed Abstract: Phosphopeptides presented by major histocompatibility complex (MHC) class I have been regarded as a pivotal type of cancer neoantigens that are recognized by T cells. The structural basis of single-phosphorylated peptide presentation has been well studied. Diphosphorylation with one interval between two sites is one of the prevalent forms of multisite-phosphorylated peptides. Herein, we determined the molecular basis of presentation of two P4/P6 double pS-containing peptides by HLA-B27 and compared them with unmodified and single-phosphorylated peptide complexes. These data clarified not only the HLA allele-specific presentation of phosphopeptides by MHC class I molecules but also the cooperativity of peptide conformation within P4 and P6 phosphorylation sites. The phosphorylation of P6 site can influence the binding mode of P4 phosphorylated site to HLA-B27. And we found the diphospho-dependent attenuated effect of peptide binding affinity. This study provides insights into the MHC presentation features of diphosphopeptides, which is different from monophosphopeptides.

PubMed: 35310951
DOI: 10.1016/j.isci.2022.104013

Experimental method

X-RAY DIFFRACTION (1.81 Å)