1xu1

The crystal structure of APRIL bound to TACIThe crystal structure of APRIL bound to TACI

Structural highlights 1xu1 is a 6 chain structure with sequence from Human and Lk3 transgenic mice. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: Related: 1u5x, 1u5y, 1u5z, 1xu2, 1xut Gene: Tnfsf13, APRIL (LK3 transgenic mice), TNFRSF13B, TACI (HUMAN) Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Disease [TR13B_HUMAN] Defects in TNFRSF13B are the cause of immunodeficiency common variable type 2 (CVID2) [MIM:240500]. CVID2 is a primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen. The defect results from a failure of B-cell differentiation and impaired secretion of immunoglobulins; the numbers of circulating B-cells is usually in the normal range, but can be low. Defects in TNFRSF13B are a cause of immunoglobulin A deficiency 2 (IGAD2) [MIM:609529]. Selective deficiency of immunoglobulin A (IGAD) is the most common form of primary immunodeficiency, with an incidence of approximately 1 in 600 individuals in the western world. Individuals with symptomatic IGAD often have deficiency of IgG subclasses or decreased antibody response to carbohydrate antigens such as pneumococcal polysaccharide vaccine. Individuals with IGAD also suffer from recurrent sinopulmonary and gastrointestinal infections and have an increased incidence of autoimmune disorders and of lymphoid and non-lymphoid malignancies. In vitro studies have suggested that some individuals with IGAD have impaired isotype class switching to IgA and others may have a post-switch defect. IGAD and CVID have been known to coexist in families. Some individuals initially present with IGAD1 and then develop CVID. These observations suggest that some cases of IGAD and CVID may have a common etiology. Function [TR13B_HUMAN] Receptor for TNFSF13/APRIL and TNFSF13B/TALL1/BAFF/BLYS that binds both ligands with similar high affinity. Mediates calcineurin-dependent activation of NF-AT, as well as activation of NF-kappa-B and AP-1. Involved in the stimulation of B- and T-cell function and the regulation of humoral immunity. 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 TACI is a member of the tumor necrosis factor receptor superfamily and serves as a key regulator of B cell function. TACI binds two ligands, APRIL and BAFF, with high affinity and contains two cysteine-rich domains (CRDs) in its extracellular region; in contrast, BCMA and BR3, the other known high affinity receptors for APRIL and BAFF, respectively, contain only a single or partial CRD. However, another form of TACI exists wherein the N-terminal CRD is removed by alternative splicing. We find that this shorter form is capable of ligand-induced cell signaling and that the second CRD alone (TACI_d2) contains full affinity for both ligands. Furthermore, we report the solution structure and alanine-scanning mutagenesis of TACI_d2 along with co-crystal structures of APRIL.TACI_d2 and APRIL.BCMA complexes that together reveal the mechanism by which TACI engages high affinity ligand binding through a single CRD, and we highlight sources of ligand-receptor specificity within the APRIL/BAFF system. Structures of APRIL-receptor complexes: like BCMA, TACI employs only a single cysteine-rich domain for high affinity ligand binding.,Hymowitz SG, Patel DR, Wallweber HJ, Runyon S, Yan M, Yin J, Shriver SK, Gordon NC, Pan B, Skelton NJ, Kelley RF, Starovasnik MA J Biol Chem. 2005 Feb 25;280(8):7218-27. Epub 2004 Nov 12. PMID:15542592 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Tumor necrosis factor ligand superfamily Tumor necrosis factor receptor

spinqualitylabelsall models 1xu1, resolution 1.90Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image