8VSP

Cryo-EM structure of human invariant chain in complex with HLA-DQ

Summary for 8VSP

• Entry DOI: 10.2210/pdb8vsp/pdb
• EMDB information: 43501
• Descriptor: HLA class II histocompatibility antigen, DQ alpha 1 chain, HLA class II histocompatibility antigen, DQ beta 1 chain, HLA class II histocompatibility antigen gamma chain, ... (4 entities in total)
• Functional Keywords: antigen presentation, membrane protein, trimeric complex, immune system
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 9
• Total formula weight: 301564.10

Authors

Wang, N.,Caveney, N.A.,Jude, K.M.,Garcia, K.C. (deposition date: 2024-01-24, release date: 2024-05-08, Last modification date: 2024-11-06)

Primary citation

Wang, N.,Waghray, D.,Caveney, N.A.,Jude, K.M.,Garcia, K.C.
Structural insights into human MHC-II association with invariant chain.
Proc.Natl.Acad.Sci.USA, 121:e2403031121-e2403031121, 2024

PubMed Abstract: The loading of processed peptides on to major histocompatibility complex II (MHC-II) molecules for recognition by T cells is vital to cell-mediated adaptive immunity. As part of this process, MHC-II associates with the invariant chain (Ii) during biosynthesis in the endoplasmic reticulum to prevent premature peptide loading and to serve as a scaffold for subsequent proteolytic processing into MHC-II-CLIP. Cryo-electron microscopy structures of full-length Human Leukocyte Antigen-DR (HLA-DR) and HLA-DQ complexes associated with Ii, resolved at 3.0 to 3.1 Å, elucidate the trimeric assembly of the HLA/Ii complex and define atomic-level interactions between HLA, Ii transmembrane domains, loop domains, and class II-associated invariant chain peptides (CLIP). Together with previous structures of MHC-II peptide loading intermediates DO and DM, our findings complete the structural path governing class II antigen presentation.

PubMed: 38687785
DOI: 10.1073/pnas.2403031121

Experimental method

ELECTRON MICROSCOPY (3.12 Å)