4X6F

CD1a binary complex with sphingomyelin

Summary for 4X6F

• Entry DOI: 10.2210/pdb4x6f/pdb
• Related: 4X6B 4X6C 4X6D 4X6E
• Descriptor: T-cell surface glycoprotein CD1a, Beta-2-microglobulin, (4S,7S,23Z)-4-hydroxy-7-[(1S,2Z)-1-hydroxyhexadec-2-en-1-yl]-N,N,N-trimethyl-9-oxo-3,5-dioxa-8-aza-4-phosphadotriacont- 23-en-1-aminium 4-oxide, ... (4 entities in total)
• Functional Keywords: cd1a, immune complex, lipid antigen, tcr, immune system
• Biological source: Homo sapiens (Human); More
• Cellular location: Cell membrane; Single-pass type I membrane protein: P06126; Secreted : P61769
• Total number of polymer chains: 2
• Total formula weight: 45351.29

Authors

Birkinshaw, R.W.,Rossjohn, J. (deposition date: 2014-12-08, release date: 2015-02-04, Last modification date: 2024-10-09)

Primary citation

Birkinshaw, R.W.,Pellicci, D.G.,Cheng, T.Y.,Keller, A.N.,Sandoval-Romero, M.,Gras, S.,de Jong, A.,Uldrich, A.P.,Moody, D.B.,Godfrey, D.I.,Rossjohn, J.
alpha beta T cell antigen receptor recognition of CD1a presenting self lipid ligands.
Nat.Immunol., 16:258-266, 2015

PubMed Abstract: A central paradigm in αβ T cell-mediated immunity is the simultaneous co-recognition of antigens and antigen-presenting molecules by the αβ T cell antigen receptor (TCR). CD1a presents a broad repertoire of lipid-based antigens. We found that a prototypical autoreactive TCR bound CD1a when it was presenting a series of permissive endogenous ligands, while other lipid ligands were nonpermissive to TCR binding. The structures of two TCR-CD1a-lipid complexes showed that the TCR docked over the A' roof of CD1a in a manner that precluded direct contact with permissive ligands. Nonpermissive ligands indirectly inhibited TCR binding by disrupting the TCR-CD1a contact zone. The exclusive recognition of CD1a by the TCR represents a previously unknown mechanism whereby αβ T cells indirectly sense self antigens that are bound to an antigen-presenting molecule.

PubMed: 25642819
DOI: 10.1038/ni.3098

Experimental method

X-RAY DIFFRACTION (1.91 Å)