3uzq
From Proteopedia
Crystal structure of the dengue virus serotype 1 envelope protein domain III in complex with the variable domains of Mab 4E11
Structural highlights
FunctionPOLG_DEN1B Plays a role in virus budding by binding to membrane and gathering the viral RNA into a nucleocapsid that forms the core of a mature virus particle. During virus entry, may induce genome penetration in host cytoplasm after hemifusion induced by surface proteins. Can migrate tot cell nucleus where it modulates host functions.[UniProtKB:P17763] Prevents premature fusion activity of envelope proteins in trans Golgi by binding to envelope protein E at pH6.0. After virion release in extracellular space gets dissociated from E dimers.[UniProtKB:P17763] Acts as a chaperone for envelope protein E during intracellular virion assembly by masking and inactivating envelope protein E fusion peptide. prM is the only viral peptide matured by host furin in the trans-Golgi network. Presumably to avoid catastrophic activation of the viral fusion activity in acidic GolGi compartment prior to virion release. prM-E cleavage is ineficient, and many virions are only partially matured. These uncleaved prM would play a role in immune evasion.[UniProtKB:P17763] May play a role in virus budding. Exerts cytotoxic effects by activating a mitochondrial apoptotic pathway through M extodomain. May display a viroporin activity.[UniProtKB:P17763] Binds to host cell surface receptor and mediates fusion between viral and cellular membranes. Envelope protein is synthesized in the endoplasmic reticulum in the form of heterodimer with protein prM. They play a role in virion budding in the ER, and the newly formed immature particle is covered with 60 spikes composed of heterodimer between precursor prM and envelope protein E. The virion is transported to the Golgi apparatus where the low pH causes dissociation of PrM-E heterodimers and formation of E homodimers. prM-E cleavage is ineficient, and many virions are only partially matured. These uncleaved prM would play a role in immune evasion.[UniProtKB:P17763] Involved in immune evasion, pathogenesis and viral replication. Once cleaved off the polyprotein, is targeted to three destinations: the viral replication cycle, the plasma membrane and the extracellular compartment. May play a role in viral genome replication. Assist membrane bending and envelopment of genomic RNA at the endoplasmic reticulum. Excreted as a hexameric lipoparticle that plays a role against host immune response.[UniProtKB:P17763] Component of the viral RNA replication complex that functions in virion assembly and antagonizes the host immune response.[UniProtKB:P17763] Required cofactor for the serine protease function of NS3 (By similarity). May have membrane-destabilizing activity and form viroporins (By similarity).[UniProtKB:P17763][PROSITE-ProRule:PRU00859] Displays three enzymatic activities: serine protease, NTPase and RNA helicase. NS3 serine protease, in association with NS2B, performs its autocleavage and cleaves the polyprotein at dibasic sites in the cytoplasm: C-prM, NS2A-NS2B, NS2B-NS3, NS3-NS4A, NS4A-2K and NS4B-NS5. NS3 RNA helicase binds RNA and unwinds dsRNA in the 3' to 5' direction.[PROSITE-ProRule:PRU00860] Regulates the ATPase activity of the NS3 helicase activity. NS4A allows NS3 helicase to conserve energy during unwinding. Plays a role in the inhibition of the host innate immune response. Interacts with host MAVS and thereby prevents the interaction between RIGI and MAVS. In turn, IFN-beta production is impaired. Interacts with host AUP1 which mediates induction of lipophagy in host cells and facilitates production of virus progeny particles (By similarity).[UniProtKB:P17763][UniProtKB:P29991][UniProtKB:Q9Q6P4] Functions as a signal peptide for NS4B and is required for the interferon antagonism activity of the latter.[UniProtKB:P17763] Inhibits interferon (IFN)-induced host STAT1 phosphorylation and nuclear translocation, thereby preventing the establishment of cellular antiviral state by blocking the IFN-alpha/beta pathway.[UniProtKB:P17763] Replicates the viral (+) and (-) genome, and performs the capping of genomes in the cytoplasm. NS5 methylates viral RNA cap at guanine N-7 and ribose 2'-O positions. Besides its role in RNA genome replication, also prevents the establishment of cellular antiviral state by blocking the interferon-alpha/beta (IFN-alpha/beta) signaling pathway. Inhibits host TYK2 and STAT2 phosphorylation, thereby preventing activation of JAK-STAT signaling pathway.[UniProtKB:P17763] Publication Abstract from PubMedThe dengue virus (DENV) complex is composed of four distinct but serologically related flaviviruses, which together cause the present-day most important emerging viral disease. Although DENV infection induces lifelong immunity against viruses of the same serotype, the antibodies raised appear to contribute to severe disease in cases of heterotypic infections. Understanding the mechanisms of DENV neutralization by antibodies is, therefore, crucial for the design of vaccines that simultaneously protect against all four viruses. Here, we report a comparative, high-resolution crystallographic analysis of an "A-strand" murine monoclonal antibody, Mab 4E11, in complex with its target domain of the envelope protein from the four DENVs. Mab 4E11 is capable of neutralizing all four serotypes, and our study reveals the determinants of this cross-reactivity. The structures also highlight the mechanism by which A-strand Mabs disrupt the architecture of the mature virion, inducing premature fusion loop exposure and concomitant particle inactivation. Mechanism of dengue virus broad cross-neutralization by a monoclonal antibody.,Cockburn JJ, Navarro Sanchez ME, Fretes N, Urvoas A, Staropoli I, Kikuti CM, Coffey LL, Arenzana Seisdedos F, Bedouelle H, Rey FA Structure. 2012 Feb 8;20(2):303-14. Epub 2012 Jan 26. PMID:22285214[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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