4orz

HIV-1 Nef protein in complex with single domain antibody sdAb19 and an engineered Hck SH3 domain

spinqualitylabelsall models 4orz, resolution 2.00Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 4orz is a 3 chain structure with sequence from HIV-1 M:B_ARV2/SF2, Homo sapiens and Lama glama. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2Å Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Disease HCK_HUMAN Note=Aberrant activation of HCK by HIV-1 protein Nef enhances HIV-1 replication and contributes to HIV-1 pathogenicity. Note=Aberrant activation of HCK, e.g. by the BCR-ABL fusion protein, promotes cancer cell proliferation. Function HCK_HUMAN Non-receptor tyrosine-protein kinase found in hematopoietic cells that transmits signals from cell surface receptors and plays an important role in the regulation of innate immune responses, including neutrophil, monocyte, macrophage and mast cell functions, phagocytosis, cell survival and proliferation, cell adhesion and migration. Acts downstream of receptors that bind the Fc region of immunoglobulins, such as FCGR1A and FCGR2A, but also CSF3R, PLAUR, the receptors for IFNG, IL2, IL6 and IL8, and integrins, such as ITGB1 and ITGB2. During the phagocytic process, mediates mobilization of secretory lysosomes, degranulation, and activation of NADPH oxidase to bring about the respiratory burst. Plays a role in the release of inflammatory molecules. Promotes reorganization of the actin cytoskeleton and actin polymerization, formation of podosomes and cell protrusions. Inhibits TP73-mediated transcription activation and TP73-mediated apoptosis. Phosphorylates CBL in response to activation of immunoglobulin gamma Fc region receptors. Phosphorylates ADAM15, BCR, ELMO1, FCGR2A, GAB1, GAB2, RAPGEF1, STAT5B, TP73, VAV1 and WAS. Publication Abstract from PubMed BACKGROUND: The HIV-1 Nef protein is essential for AIDS pathogenesis by its interaction with host cell surface receptors and signaling factors. Despite its critical role as a virulence factor Nef is not targeted by current antiviral strategies. RESULTS: We have determined the crystal structure of the complex formed by a camelid single-domain antibody fragment, termed sdAb19, bound to HIV-1 Nef together with a stabilizing SH3 domain. sdAb19 forms a stoichiometric 1:1 complex with Nef and binds to a conformationally conserved surface at the C-terminus of Nef that overlaps with functionally important interaction sites involved in Nef-induced perturbations of signaling and trafficking pathways. The antibody fragment binds Nef with low nanomolar affinity, which could be attenuated to micromolar affinity range by site-directed mutagenesis of key interaction residues in sdAb19. Fusion of the SH3 domain to sdAb19, termed Neffin, leads to a significantly increased affinity for Nef and formation of a stoichiometric 2:2 Nef-Neffin complex. The 19 kDa Neffin protein inhibits all functions of Nef as CD4 and MHC-I downregulation, association with Pak2, and the increase in virus infectivity and replication. CONCLUSIONS: Together, sdAb19 and Neffin thus represent efficient tools for the rational development of antiviral strategies against HIV-1 Nef. Structural basis for the inhibition of HIV-1 Nef by a high-affinity binding single-domain antibody.,Lulf S, Matz J, Rouyez MC, Jarviluoma A, Saksela K, Benichou S, Geyer M Retrovirology. 2014 Mar 13;11(1):24. doi: 10.1186/1742-4690-11-24. PMID:24620746 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Antibody 3D structures Protein Nef Tyrosine kinase 3D structures 3D structures of non-human antibody

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