3O9W

Recognition of a Glycolipid Antigen by the iNKT Cell TCR

Summary for 3O9W

• Entry DOI: 10.2210/pdb3o9w/pdb
• Related: 2FIK 3ILQ 3O8X
• Descriptor: Antigen-presenting glycoprotein CD1d1, Beta-2-microglobulin, Valpha14 chimera (Mouse variable domain, Human T-cell receptor alpha chain C region constant domain), ... (9 entities in total)
• Functional Keywords: antigen presentation, glycolipid, nkt cells, immune system
• Biological source: Mus musculus (Mouse); More
• Total number of polymer chains: 4
• Total formula weight: 96348.88

Authors

Zajonc, D.M.,Li, Y. (deposition date: 2010-08-04, release date: 2010-09-29, Last modification date: 2024-11-27)

Primary citation

Li, Y.,Girardi, E.,Wang, J.,Yu, E.D.,Painter, G.F.,Kronenberg, M.,Zajonc, D.M.
The V alpha 14 invariant natural killer T cell TCR forces microbial glycolipids and CD1d into a conserved binding mode.
J.Exp.Med., 207:2383-2393, 2010

PubMed Abstract: Invariant natural killer T cells (iNKT cells) rapidly produce effector cytokines. In this study, we report the first crystal structures of the iNKT cell T cell receptor (TCR) bound to two natural, microbial glycolipids presented by CD1d. Binding of the TCR induced CDR3-α-dependent structural changes in the F' roof of CD1d; these changes resemble those occurring in the absence of TCR engagement when the highly potent synthetic antigen α-galactosylceramide (α-GalCer) binds CD1d. Furthermore, in the Borrelia burgdorferi α-galactosyl diacylglycerol-CD1d complex, TCR binding caused a marked repositioning of the galactose sugar into an orientation that closely resembles α-GalCer. The TCR-dependent reorientation of the sugar, together with the induced CD1d fit, may explain the weaker potency of the microbial antigens compared with α-GalCer. We propose that the TCR of iNKT cells binds with a conserved footprint onto CD1d, regardless of the bound glycolipid antigen, and that for microbial antigens this unique binding mode requires TCR-initiated conformational changes.

PubMed: 20921281
DOI: 10.1084/jem.20101335

Experimental method

X-RAY DIFFRACTION (2.8 Å)