1y6n
From Proteopedia
Crystal structure of Epstein-Barr virus IL-10 mutant (A87I) complexed with the soluble IL-10R1 chain
Structural highlights
Disease[I10R1_HUMAN] Defects in IL10RA are the cause of inflammatory bowel disease type 28 (IBD28) [MIM:613148]. It is a chronic, relapsing inflammation of the gastrointestinal tract with a complex etiology. It is subdivided into Crohn disease and ulcerative colitis phenotypes. Crohn disease may affect any part of the gastrointestinal tract from the mouth to the anus, but most frequently it involves the terminal ileum and colon. Bowel inflammation is transmural and discontinuous; it may contain granulomas or be associated with intestinal or perianal fistulas. In contrast, in ulcerative colitis, the inflammation is continuous and limited to rectal and colonic mucosal layers; fistulas and granulomas are not observed. Both diseases include extraintestinal inflammation of the skin, eyes, or joints.[1] Function[IL10H_EBVB9] Plays a role in masking infected cells for immune recognition by cytotoxic T-lymphocytes. Down-regulates the expression of the host TAP1 gene (transporter associated with antigen processing), thereby affecting the transport of peptides into the endoplasmic reticulum and subsequent peptide loading by MHC class I molecules. Inhibits IFN-gamma synthesis.[2] [3] [I10R1_HUMAN] Receptor for IL10; binds IL10 with a high affinity. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedHuman IL-10 (hIL-10) is a cytokine that modulates diverse immune responses. The Epstein-Barr virus (EBV) genome contains an IL-10 homolog (vIL-10) that shares high sequence and structural similarity with hIL-10. Although vIL-10 suppresses inflammatory responses like hIL-10, it cannot activate many other immunostimulatory functions performed by the cellular cytokine. These functional differences have been correlated with the approximately 1000-fold lower affinity of vIL-10, compared to hIL-10, for the IL-10R1 receptor chain. To define the structural basis for these observations, crystal structures of vIL-10 and a vIL-10 point mutant were determined bound to the soluble IL-10R1 receptor fragment (sIL-10R1) at 2.8 and 2.7 A resolution, respectively. The structures reveal that subtle changes in the conformation and dynamics of the vIL-10 AB and CD loops and an orientation change of vIL-10 on sIL-10R1 are the main factors responsible for vIL-10's reduced affinity for sIL-10R1 and its distinct biological profile. Same structure, different function crystal structure of the Epstein-Barr virus IL-10 bound to the soluble IL-10R1 chain.,Yoon SI, Jones BC, Logsdon NJ, Walter MR Structure. 2005 Apr;13(4):551-64. PMID:15837194[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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