View source for 6izy


==The RNA-dependent RNA polymerase domain of dengue 2 NS5==
<StructureSection load='6izy' size='340' side='right'caption='[[6izy]], [[Resolution|resolution]] 2.11&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6izy]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Dengue_virus_2 Dengue virus 2]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6IZY OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6IZY FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.11&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CO:COBALT+(II)+ION'>CO</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=6izy FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6izy OCA], [https://pdbe.org/6izy PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6izy RCSB], [https://www.ebi.ac.uk/pdbsum/6izy PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6izy ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/POLG_DEN2N POLG_DEN2N] Capsid protein C self-assembles to form an icosahedral capsid about 30 nm in diameter. The capsid encapsulates the genomic RNA (By similarity).  prM acts as a chaperone for envelope protein E during intracellular virion assembly by masking and inactivating envelope protein E fusion peptide. prM is matured in the last step of virion assembly, presumably to avoid catastrophic activation of the viral fusion peptide induced by the acidic pH of the trans-Golgi network. After cleavage by host furin, the pr peptide is released in the extracellular medium and small envelope protein M and envelope protein E homodimers are dissociated (By similarity).  Envelope protein E binding to host cell surface receptor is followed by virus internalization through clathrin-mediated endocytosis. Envelope protein E is subsequently involved in membrane fusion between virion and host late endosomes. Synthesized as a homodimer with prM which acts as a chaperone for envelope protein E. After cleavage of prM, envelope protein E dissociate from small envelope protein M and homodimerizes (By similarity).  Non-structural protein 1 is involved in virus replication and regulation of the innate immune response. Soluble and membrane-associated NS1 may activate human complement and induce host vascular leakage. This effect might explain the clinical manifestations of dengue hemorrhagic fever and dengue shock syndrome (By similarity).  Non-structural protein 2A may be involved viral RNA replication and capsid assembly.  Non-structural protein 2B is a required cofactor for the serine protease function of NS3.[PROSITE-ProRule:PRU00859]  Serine protease NS3 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 (By similarity).[PROSITE-ProRule:PRU00860]  Non-structural protein 4A induces host endoplasmic reticulum membrane rearrangements leading to the formation of virus-induced membranous vesicles hosting the dsRNA and polymerase, functioning as a replication complex. NS4A might also regulate the ATPase activity of the NS3 helicase (By similarity).  Peptide 2k functions as a signal peptide for NS4B and is required for the interferon antagonism activity of the latter.  Non-structural protein 4B 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.  RNA-directed RNA polymerase NS5 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 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 (By similarity).[PROSITE-ProRule:PRU00539]
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== Publication Abstract from PubMed ==
Dengue is a mosquito-borne viral infection that has spread globally in recent years. Around half of the world's population, especially in the tropics and subtropics, is at risk of infection. Every year, 50-100 million clinical cases are reported, and more than 500,000 patients develop the symptoms of severe dengue infection: dengue haemorrhagic fever and dengue shock syndrome, which threaten life in Asia and Latin America. No antiviral drug for dengue is available. The dengue virus (DENV) non-structural protein 5 (NS5), which possesses the RNA-dependent RNA polymerase (RdRp) activity and is responsible for viral replication and transcription, is an attractive target for anti-dengue drug development. In the present study, 16,240 small-molecule compounds in a fragment library were screened for their capabilities to inhibit the DENV type 2 (DENV2) RdRp activities in vitro. Based on in cellulo antiviral and cytotoxity assays, we selected the compound RK-0404678 with the EC50 value of 6.0 muM for DENV2. Crystallographic analyses revealed two unique binding sites for RK-0404678 within the RdRp, which are conserved in flavivirus NS5 proteins. No resistant viruses emerged after nine rounds of serial passage of DENV2 in the presence of RK-0404678, suggesting the high genetic barrier of this compound to the emergence of a resistant virus. Collectively, RK-0404678 and its binding sites provide a new framework for antiviral drug development.

Discovery of a small molecule inhibitor targeting dengue virus NS5 RNA-dependent RNA polymerase.,Shimizu H, Saito A, Mikuni J, Nakayama EE, Koyama H, Honma T, Shirouzu M, Sekine SI, Shioda T PLoS Negl Trop Dis. 2019 Nov 18;13(11):e0007894. doi:, 10.1371/journal.pntd.0007894. eCollection 2019 Nov. PMID:31738758<ref>PMID:31738758</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6izy" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Dengue virus 2]]
[[Category: Large Structures]]
[[Category: Sekine S]]
[[Category: Shimizu H]]