4en3: Difference between revisions
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==Crystal structure of a human Valpha24(-) NKT TCR in complex with CD1d/alpha-galactosylceramide== | |||
<StructureSection load='4en3' size='340' side='right' caption='[[4en3]], [[Resolution|resolution]] 2.57Å' scene=''> | |||
{ | == Structural highlights == | ||
<table><tr><td colspan='2'>[[4en3]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4EN3 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4EN3 FirstGlance]. <br> | |||
==Disease== | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=AGH:N-{(1S,2R,3S)-1-[(ALPHA-D-GALACTOPYRANOSYLOXY)METHYL]-2,3-DIHYDROXYHEPTADECYL}HEXACOSANAMIDE'>AGH</scene>, <scene name='pdbligand=FUC:ALPHA-L-FUCOSE'>FUC</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene></td></tr> | ||
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">CD1D ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]), B2M, CDABP0092, HDCMA22P ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens])</td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4en3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4en3 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4en3 RCSB], [http://www.ebi.ac.uk/pdbsum/4en3 PDBsum]</span></td></tr> | |||
</table> | |||
== Disease == | |||
[[http://www.uniprot.org/uniprot/B2MG_HUMAN B2MG_HUMAN]] Defects in B2M are the cause of hypercatabolic hypoproteinemia (HYCATHYP) [MIM:[http://omim.org/entry/241600 241600]]. Affected individuals show marked reduction in serum concentrations of immunoglobulin and albumin, probably due to rapid degradation.<ref>PMID:16549777</ref> Note=Beta-2-microglobulin may adopt the fibrillar configuration of amyloid in certain pathologic states. The capacity to assemble into amyloid fibrils is concentration dependent. Persistently high beta(2)-microglobulin serum levels lead to amyloidosis in patients on long-term hemodialysis.<ref>PMID:3532124</ref> <ref>PMID:1336137</ref> <ref>PMID:7554280</ref> <ref>PMID:4586824</ref> <ref>PMID:8084451</ref> <ref>PMID:12119416</ref> <ref>PMID:12796775</ref> <ref>PMID:16901902</ref> <ref>PMID:16491088</ref> <ref>PMID:17646174</ref> <ref>PMID:18835253</ref> <ref>PMID:18395224</ref> <ref>PMID:19284997</ref> | [[http://www.uniprot.org/uniprot/B2MG_HUMAN B2MG_HUMAN]] Defects in B2M are the cause of hypercatabolic hypoproteinemia (HYCATHYP) [MIM:[http://omim.org/entry/241600 241600]]. Affected individuals show marked reduction in serum concentrations of immunoglobulin and albumin, probably due to rapid degradation.<ref>PMID:16549777</ref> Note=Beta-2-microglobulin may adopt the fibrillar configuration of amyloid in certain pathologic states. The capacity to assemble into amyloid fibrils is concentration dependent. Persistently high beta(2)-microglobulin serum levels lead to amyloidosis in patients on long-term hemodialysis.<ref>PMID:3532124</ref> <ref>PMID:1336137</ref> <ref>PMID:7554280</ref> <ref>PMID:4586824</ref> <ref>PMID:8084451</ref> <ref>PMID:12119416</ref> <ref>PMID:12796775</ref> <ref>PMID:16901902</ref> <ref>PMID:16491088</ref> <ref>PMID:17646174</ref> <ref>PMID:18835253</ref> <ref>PMID:18395224</ref> <ref>PMID:19284997</ref> | ||
== Function == | |||
[[http://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> [[http://www.uniprot.org/uniprot/B2MG_HUMAN B2MG_HUMAN]] Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system. | |||
<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> | |||
==See Also== | ==See Also== | ||
*[[Beta-2 microglobulin|Beta-2 microglobulin]] | *[[Beta-2 microglobulin|Beta-2 microglobulin]] | ||
== References == | |||
== | <references/> | ||
__TOC__ | |||
</StructureSection> | |||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Adams, E J | [[Category: Adams, E J]] | ||
[[Category: Lopez-Sagaseta, J]] | [[Category: Lopez-Sagaseta, J]] | ||
[[Category: Antigen presentation-recognition]] | [[Category: Antigen presentation-recognition]] |