This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
4en3
From Proteopedia
(Difference between revisions)
| Line 10: | Line 10: | ||
== Function == | == Function == | ||
[https://www.uniprot.org/uniprot/CD1D_HUMAN CD1D_HUMAN] Antigen-presenting protein that binds self and non-self glycolipids and presents them to T-cell receptors on natural killer T-cells.<ref>PMID:17475845</ref> | [https://www.uniprot.org/uniprot/CD1D_HUMAN CD1D_HUMAN] Antigen-presenting protein that binds self and non-self glycolipids and presents them to T-cell receptors on natural killer T-cells.<ref>PMID:17475845</ref> | ||
| - | <div style="background-color:#fffaf0;"> | ||
| - | == Publication Abstract from PubMed == | ||
| - | CD1d-mediated presentation of glycolipid antigens to T cells is capable of initiating powerful immune responses that can have a beneficial impact on many diseases. Molecular analyses have recently detailed the lipid antigen recognition strategies utilized by the invariant Valpha24-Jalpha18 TCR rearrangements of iNKT cells, which comprise a subset of the human CD1d-restricted T cell population. In contrast, little is known about how lipid antigens are recognized by functionally distinct CD1d-restricted T cells bearing different TCRalpha chain rearrangements. Here we present crystallographic and biophysical analyses of alpha-galactosylceramide (alpha-GalCer) recognition by a human CD1d-restricted TCR that utilizes a Valpha3.1-Jalpha18 rearrangement and displays a more restricted specificity for alpha-linked glycolipids than that of iNKT TCRs. Despite having sequence divergence in the CDR1alpha and CDR2alpha loops, this TCR employs a convergent recognition strategy to engage CD1d/alphaGalCer, with a binding affinity ( approximately 2 microM) almost identical to that of an iNKT TCR used in this study. The CDR3alpha loop, similar in sequence to iNKT-TCRs, engages CD1d/alphaGalCer in a similar position as that seen with iNKT-TCRs, however fewer actual contacts are made. Instead, the CDR1alpha loop contributes important contacts to CD1d/alphaGalCer, with an emphasis on the 4'OH of the galactose headgroup. This is consistent with the inability of Valpha24- T cells to respond to alpha-glucosylceramide, which differs from alphaGalCer in the position of the 4'OH. These data illustrate how fine specificity for a lipid containing alpha-linked galactose is achieved by a TCR structurally distinct from that of iNKT cells. | ||
| - | |||
| - | The molecular basis for recognition of CD1d/alpha-galactosylceramide by a human non-Valpha24 T cell receptor.,Lopez-Sagaseta J, Kung JE, Savage PB, Gumperz J, Adams EJ PLoS Biol. 2012;10(10):e1001412. doi: 10.1371/journal.pbio.1001412. Epub 2012 Oct, 23. PMID:23109910<ref>PMID:23109910</ref> | ||
| - | |||
| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| - | </div> | ||
| - | <div class="pdbe-citations 4en3" style="background-color:#fffaf0;"></div> | ||
==See Also== | ==See Also== | ||
Current revision
Crystal structure of a human Valpha24(-) NKT TCR in complex with CD1d/alpha-galactosylceramide
| |||||||||||
