Structural highlights
Function
CXAR_HUMAN Component of the epithelial apical junction complex that is essential for the tight junction integrity. Proposed to function as a homophilic cell adhesion molecule. Recruits MPDZ to intercellular contact sites. Probably involved in transepithelial migration of polymorphonuclear leukocytes (PMN) through adhesive interactions with AMICA1/JAML located in the plasma membrane of PMN.[1] [2] [3] [4]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
BACKGROUND: The coxsackievirus and adenovirus receptor (CAR) comprises two extracellular immunoglobulin domains, a transmembrane helix and a C-terminal intracellular domain. The amino-terminal immunoglobulin domain (D1) of CAR is necessary and sufficient for adenovirus binding, whereas the site of coxsackievirus attachment has not yet been localized. The normal cellular role of CAR is currently unknown, although CAR was recently proposed to function as a homophilic cell adhesion molecule. RESULTS: The human CAR D1 domain was bacterially expressed and crystallized. The structure was solved by molecular replacement using the structure of CAR D1 bound to the adenovirus type 12 fiber head and refined to 1.7 A resolution, including individual anisotropic temperature factors. The two CAR D1 structures are virtually identical, apart from the BC, C"D, and FG loops that are involved both in fiber head binding and homodimerization in the crystal. Analytical equilibrium ultracentrifugation shows that a dimer also exists in solution, with a dissociation constant of 16 microM. CONCLUSIONS: The CAR D1 domain forms homodimers in the crystal using the same GFCC'C" surface that interacts with the adenovirus fiber head. The homodimer is very similar to the CD2 D1-CD58 D1 heterodimer. CAR D1 also forms dimers in solution with a dissociation constant typical of other cell adhesion complexes. These results are consistent with reports that CAR may function physiologically as a homophilic cell adhesion molecule in the developing mouse brain. Adenovirus may thus have recruited an existing and conserved interaction surface of CAR to use for its own cell attachment.
Dimeric structure of the coxsackievirus and adenovirus receptor D1 domain at 1.7 A resolution.,van Raaij MJ, Chouin E, van der Zandt H, Bergelson JM, Cusack S Structure. 2000 Nov 15;8(11):1147-55. PMID:11080637[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Tomko RP, Xu R, Philipson L. HCAR and MCAR: the human and mouse cellular receptors for subgroup C adenoviruses and group B coxsackieviruses. Proc Natl Acad Sci U S A. 1997 Apr 1;94(7):3352-6. PMID:9096397
- ↑ Cohen CJ, Shieh JT, Pickles RJ, Okegawa T, Hsieh JT, Bergelson JM. The coxsackievirus and adenovirus receptor is a transmembrane component of the tight junction. Proc Natl Acad Sci U S A. 2001 Dec 18;98(26):15191-6. Epub 2001 Dec 4. PMID:11734628 doi:10.1073/pnas.261452898
- ↑ Walters RW, Freimuth P, Moninger TO, Ganske I, Zabner J, Welsh MJ. Adenovirus fiber disrupts CAR-mediated intercellular adhesion allowing virus escape. Cell. 2002 Sep 20;110(6):789-99. PMID:12297051
- ↑ Zen K, Liu Y, McCall IC, Wu T, Lee W, Babbin BA, Nusrat A, Parkos CA. Neutrophil migration across tight junctions is mediated by adhesive interactions between epithelial coxsackie and adenovirus receptor and a junctional adhesion molecule-like protein on neutrophils. Mol Biol Cell. 2005 Jun;16(6):2694-703. Epub 2005 Mar 30. PMID:15800062 doi:E05-01-0036
- ↑ van Raaij MJ, Chouin E, van der Zandt H, Bergelson JM, Cusack S. Dimeric structure of the coxsackievirus and adenovirus receptor D1 domain at 1.7 A resolution. Structure. 2000 Nov 15;8(11):1147-55. PMID:11080637
