View source for 1xiw

[[Image:1xiw.gif|left|200px]]

 {{Structure
|PDB= 1xiw |SIZE=350|CAPTION= <scene name='initialview01'>1xiw</scene>, resolution 1.90&Aring;
|SITE= 
|LIGAND= 
|ACTIVITY= 
|GENE= CD3E, T3E ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]), CD3D, T3D ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]), UCHT1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=10090 Mus musculus])
}}

'''Crystal structure of human CD3-e/d dimer in complex with a UCHT1 single-chain antibody fragment'''


==Overview==
The alpha/beta T cell receptor complex transmits signals from MHC/peptide antigens through a set of constitutively associated signaling molecules, including CD3-epsilon/gamma and CD3-epsilon/delta. We report the crystal structure at 1.9-A resolution of a complex between a human CD3-epsilon/delta ectodomain heterodimer and a single-chain fragment of the UCHT1 antibody. CD3-epsilon/delta and CD3-epsilon/gamma share a conserved interface between the Ig-fold ectodomains, with parallel packing of the two G strands. CD3-delta has a more electronegative surface and a more compact Ig fold than CD3-gamma; thus, the two CD3 heterodimers have distinctly different molecular surfaces. The UCHT1 antibody binds near an acidic region of CD3-epsilon opposite the dimer interface, occluding this region from direct interaction with the TCR. This immunodominant epitope may be a uniquely accessible surface in the TCR/CD3 complex, because there is overlap between the binding site of the UCHT1 and OKT3 antibodies. Determination of the CD3-epsilon/delta structure completes the set of TCR/CD3 globular ectodomains and contributes information about exposed CD3 surfaces.

==About this Structure==
1XIW is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XIW OCA]. 

==Reference==
Crystal structure of a human CD3-epsilon/delta dimer in complex with a UCHT1 single-chain antibody fragment., Arnett KL, Harrison SC, Wiley DC, Proc Natl Acad Sci U S A. 2004 Nov 16;101(46):16268-73. Epub 2004 Nov 8. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/15534202 15534202]
[[Category: Homo sapiens]]
[[Category: Mus musculus]]
[[Category: Protein complex]]
[[Category: Arnett, K L.]]
[[Category: Harrison, S C.]]
[[Category: Wiley, D C.]]
[[Category: antibody-antigen complex]]
[[Category: cd3-delta]]
[[Category: cd3-epsilon]]
[[Category: immunoglobulin fold]]
[[Category: ucht1-scfv]]

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 15:10:29 2008''