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| - | ==Structural Basis for RNA Recognition and Activation of RIG-I==
| + | #REDIRECT [[5e3h]] This PDB entry is obsolete and replaced by 5e3h |
| - | <StructureSection load='3tmi' size='340' side='right' caption='[[3tmi]], [[Resolution|resolution]] 2.90Å' scene=''>
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| - | == Structural highlights ==
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| - | <table><tr><td colspan='2'>[[3tmi]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3TMI OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3TMI FirstGlance]. <br>
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| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=BEF:BERYLLIUM+TRIFLUORIDE+ION'>BEF</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
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| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">DDX58, RIG-I ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens])</td></tr>
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| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/RNA_helicase RNA helicase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.4.13 3.6.4.13] </span></td></tr>
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| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3tmi FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3tmi OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3tmi RCSB], [http://www.ebi.ac.uk/pdbsum/3tmi PDBsum]</span></td></tr>
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| - | </table>
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| - | == Function ==
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| - | [[http://www.uniprot.org/uniprot/DDX58_HUMAN DDX58_HUMAN]] Innate immune receptor which acts as a cytoplasmic sensor of viral nucleic acids and plays a major role in sensing viral infection and in the activation of a cascade of antiviral responses including the induction of type I interferons and proinflammatory cytokines. Its ligands include: 5'-triphosphorylated ssRNA and dsRNA and short dsRNA (<1 kb in length). In addition to the 5'-triphosphate moiety, blunt-end base pairing at the 5'-end of the RNA is very essential. Overhangs at the non-triphosphorylated end of the dsRNA RNA have no major impact on its activity. A 3'overhang at the 5'triphosphate end decreases and any 5'overhang at the 5' triphosphate end abolishes its activity. Upon ligand binding it associates with mitochondria antiviral signaling protein (MAVS/IPS1) which activates the IKK-related kinases: TBK1 and IKBKE which phosphorylate interferon regulatory factors: IRF3 and IRF7 which in turn activate transcription of antiviral immunological genes, including interferons (IFNs); IFN-alpha and IFN-beta. Detects both positive and negative strand RNA viruses including members of the families Paramyxoviridae: Human respiratory syncytial virus and measles virus (MeV), Rhabdoviridae: vesicular stomatitis virus (VSV), Orthomyxoviridae: influenza A and B virus, Flaviviridae: Japanese encephalitis virus (JEV), hepatitis C virus (HCV), dengue virus (DENV) and west Nile virus (WNV). It also detects rotavirus and reovirus. Also involved in antiviral signaling in response to viruses containing a dsDNA genome such as Epstein-Barr virus (EBV). Detects dsRNA produced from non-self dsDNA by RNA polymerase III, such as Epstein-Barr virus-encoded RNAs (EBERs). May play important roles in granulocyte production and differentiation, bacterial phagocytosis and in the regulation of cell migration.<ref>PMID:15208624</ref> <ref>PMID:16125763</ref> <ref>PMID:15708988</ref> <ref>PMID:16153868</ref> <ref>PMID:16127453</ref> <ref>PMID:17190814</ref> <ref>PMID:18636086</ref> <ref>PMID:19631370</ref> <ref>PMID:19576794</ref> <ref>PMID:19122199</ref> <ref>PMID:19211564</ref> <ref>PMID:19609254</ref> <ref>PMID:21742966</ref>
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| - | <div style="background-color:#fffaf0;">
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| - | == Publication Abstract from PubMed ==
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| - | Retinoic-acid-inducible gene-I (RIG-I; also known as DDX58) is a cytoplasmic pathogen recognition receptor that recognizes pathogen-associated molecular pattern (PAMP) motifs to differentiate between viral and cellular RNAs. RIG-I is activated by blunt-ended double-stranded (ds)RNA with or without a 5'-triphosphate (ppp), by single-stranded RNA marked by a 5'-ppp and by polyuridine sequences. Upon binding to such PAMP motifs, RIG-I initiates a signalling cascade that induces innate immune defences and inflammatory cytokines to establish an antiviral state. The RIG-I pathway is highly regulated and aberrant signalling leads to apoptosis, altered cell differentiation, inflammation, autoimmune diseases and cancer. The helicase and repressor domains (RD) of RIG-I recognize dsRNA and 5'-ppp RNA to activate the two amino-terminal caspase recruitment domains (CARDs) for signalling. Here, to understand the synergy between the helicase and the RD for RNA binding, and the contribution of ATP hydrolysis to RIG-I activation, we determined the structure of human RIG-I helicase-RD in complex with dsRNA and an ATP analogue. The helicase-RD organizes into a ring around dsRNA, capping one end, while contacting both strands using previously uncharacterized motifs to recognize dsRNA. Small-angle X-ray scattering, limited proteolysis and differential scanning fluorimetry indicate that RIG-I is in an extended and flexible conformation that compacts upon binding RNA. These results provide a detailed view of the role of helicase in dsRNA recognition, the synergy between the RD and the helicase for RNA binding and the organization of full-length RIG-I bound to dsRNA, and provide evidence of a conformational change upon RNA binding. The RIG-I helicase-RD structure is consistent with dsRNA translocation without unwinding and cooperative binding to RNA. The structure yields unprecedented insight into innate immunity and has a broader impact on other areas of biology, including RNA interference and DNA repair, which utilize homologous helicase domains within DICER and FANCM.
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| - | Structural basis of RNA recognition and activation by innate immune receptor RIG-I.,Jiang F, Ramanathan A, Miller MT, Tang GQ, Gale M, Patel SS, Marcotrigiano J Nature. 2011 Sep 25. doi: 10.1038/nature10537. PMID:21947008<ref>PMID:21947008</ref>
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| - | </div>
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| - | ==See Also==
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| - | *[[Helicase|Helicase]]
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| - | == References ==
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| - | <references/>
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| - | __TOC__
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| - | </StructureSection>
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| - | [[Category: Homo sapiens]]
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| - | [[Category: RNA helicase]]
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| - | [[Category: Jiang, F]]
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| - | [[Category: Marcotrigiano, J]]
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| - | [[Category: Miller, M T]]
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| - | [[Category: Atp binding and rna binding]]
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| - | [[Category: Hydrolase-rna complex]]
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| - | [[Category: Innate immune receptor]]
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| - | [[Category: Rna dexh/d box helicase/atpase]]
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