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Crystal structure of autoinhibited form of tandem SH3 domain of p47phoxCrystal structure of autoinhibited form of tandem SH3 domain of p47phox
Structural highlights
DiseaseNCF1_HUMAN Defects in NCF1 are the cause of chronic granulomatous disease autosomal recessive cytochrome-b-positive type 1 (CGD1) [MIM:233700. Chronic granulomatous disease is a genetically heterogeneous disorder characterized by the inability of neutrophils and phagocytes to kill microbes that they have ingested. Patients suffer from life-threatening bacterial/fungal infections.[1] [2] FunctionNCF1_HUMAN NCF2, NCF1, and a membrane bound cytochrome b558 are required for activation of the latent NADPH oxidase (necessary for superoxide production).[3] 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 PubMedThe phagocyte NADPH oxidase is a multisubunit enzyme responsible for the production of reactive oxygen species. p47(phox) is a cytosolic component of the NADPH oxidase and plays an important role in the assembly of the activated complex. The structural determination of the tandem SH3 domains of p47(phox) is crucial for elucidation of the molecular mechanism of the activation of p47(phox). We determined the X-ray crystal structure of the tandem SH3 domains with the polybasic/autoinhibitory region (PBR/AIR) of p47(phox). The GAPPR sequence involved in PBR/AIR forms a left-handed polyproline type-II helix (PPII) and interacts with the conserved SH3 binding surfaces of the SH3 domains simultaneously. These SH3 domains are related by a 2-fold pseudosymmetry axis at the centre of the binding groove and interact with the single PPII helix formed by the GAPPR sequence with opposite orientation. In addition, a number of intra-molecular interactions among the SH3 domains, PBR/AIR and the linker tightly hold the architecture of the tandem SH3 domains into the compact structure and stabilize the autoinhibited form synergistically. Phosphorylation of the serine residues in PBR/AIR could destabilize and successively release the intra-molecular interactions. Thus, the overall structure could be rearranged from the autoinhibitory conformation to the active conformation and the PPII ligand binding surfaces on the SH3 domains are now unmasked, which enables their interaction with the target sequence in p22(phox). A molecular mechanism for autoinhibition of the tandem SH3 domains of p47phox, the regulatory subunit of the phagocyte NADPH oxidase.,Yuzawa S, Suzuki NN, Fujioka Y, Ogura K, Sumimoto H, Inagaki F Genes Cells. 2004 May;9(5):443-56. PMID:15147273[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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