2ahm: Difference between revisions
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== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[2ahm]] is a 8 chain structure with sequence from [http://en.wikipedia.org/wiki/Sars_coronavirus Sars coronavirus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AHM OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2AHM FirstGlance]. <br> | <table><tr><td colspan='2'>[[2ahm]] is a 8 chain structure with sequence from [http://en.wikipedia.org/wiki/Sars_coronavirus Sars coronavirus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AHM OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2AHM FirstGlance]. <br> | ||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>< | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> | ||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2ahm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ahm OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2ahm RCSB], [http://www.ebi.ac.uk/pdbsum/2ahm PDBsum]</span></td></tr> | <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=2ahm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ahm OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2ahm RCSB], [http://www.ebi.ac.uk/pdbsum/2ahm PDBsum]</span></td></tr> | ||
<table> | </table> | ||
== Function == | |||
[[http://www.uniprot.org/uniprot/R1AB_CVHSA R1AB_CVHSA]] The replicase polyprotein of coronaviruses is a multifunctional protein: it contains the activities necessary for the transcription of negative stranded RNA, leader RNA, subgenomic mRNAs and progeny virion RNA as well as proteinases responsible for the cleavage of the polyprotein into functional products (By similarity).<ref>PMID:17024178</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> The papain-like proteinase (PL-PRO) is responsible for the cleavages located at the N-terminus of replicase polyprotein. In addition, PL-PRO possesses a deubiquitinating/deISGylating activity and processes both 'Lys-48'- and 'Lys-63'-linked polyubiquitin chains from cellular substrates. Antagonizes innate immune induction of type I interferon by blocking the phosphorylation, dimerization and subsequent nuclear translocation of host IRF-3.<ref>PMID:17024178</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> The main proteinase 3CL-PRO is responsible for the majority of cleavages as it cleaves the C-terminus of replicase polyprotein at 11 sites. Recognizes substrates containing the core sequence [ILMVF]-Q-|-[SGACN]. Inhibited by the substrate-analog Cbz-Val-Asn-Ser-Thr-Leu-Gln-CMK (By similarity). Also contains an ADP-ribose-1''-phosphate (ADRP)-binding function.<ref>PMID:17024178</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> The helicase which contains a zinc finger structure displays RNA and DNA duplex-unwinding activities with 5' to 3' polarity. Its ATPase activity is strongly stimulated by poly(U), poly(dT), poly(C), poly(dA), but not by poly(G). Activity of helicase is dependent on magnesium.<ref>PMID:17024178</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> The exoribonuclease acts on both ssRNA and dsRNA in a 3' to 5' direction.<ref>PMID:17024178</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> Nsp7-nsp8 hexadecamer may possibly confer processivity to the polymerase, maybe by binding to dsRNA or by producing primers utilized by the latter.<ref>PMID:17024178</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> Nsp9 is a ssRNA-binding protein.<ref>PMID:17024178</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> NendoU is a Mn(2+)-dependent, uridylate-specific enzyme, which leaves 2'-3'-cyclic phosphates 5' to the cleaved bond.<ref>PMID:17024178</ref> <ref>PMID:17692280</ref> <ref>PMID:19369340</ref> | |||
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
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</StructureSection> | </StructureSection> | ||
[[Category: Sars coronavirus]] | [[Category: Sars coronavirus]] | ||
[[Category: Bartlam, M | [[Category: Bartlam, M]] | ||
[[Category: Rao, Z | [[Category: Rao, Z]] | ||
[[Category: Sun, F | [[Category: Sun, F]] | ||
[[Category: Zhai, Y J | [[Category: Zhai, Y J]] | ||
[[Category: Coronavirus]] | [[Category: Coronavirus]] | ||
[[Category: Hexadecamer]] | [[Category: Hexadecamer]] |
Revision as of 18:52, 25 December 2014
Crystal structure of SARS-CoV super complex of non-structural proteins: the hexadecamerCrystal structure of SARS-CoV super complex of non-structural proteins: the hexadecamer
Structural highlights
Function[R1AB_CVHSA] The replicase polyprotein of coronaviruses is a multifunctional protein: it contains the activities necessary for the transcription of negative stranded RNA, leader RNA, subgenomic mRNAs and progeny virion RNA as well as proteinases responsible for the cleavage of the polyprotein into functional products (By similarity).[1] [2] [3] The papain-like proteinase (PL-PRO) is responsible for the cleavages located at the N-terminus of replicase polyprotein. In addition, PL-PRO possesses a deubiquitinating/deISGylating activity and processes both 'Lys-48'- and 'Lys-63'-linked polyubiquitin chains from cellular substrates. Antagonizes innate immune induction of type I interferon by blocking the phosphorylation, dimerization and subsequent nuclear translocation of host IRF-3.[4] [5] [6] The main proteinase 3CL-PRO is responsible for the majority of cleavages as it cleaves the C-terminus of replicase polyprotein at 11 sites. Recognizes substrates containing the core sequence [ILMVF]-Q-|-[SGACN]. Inhibited by the substrate-analog Cbz-Val-Asn-Ser-Thr-Leu-Gln-CMK (By similarity). Also contains an ADP-ribose-1-phosphate (ADRP)-binding function.[7] [8] [9] The helicase which contains a zinc finger structure displays RNA and DNA duplex-unwinding activities with 5' to 3' polarity. Its ATPase activity is strongly stimulated by poly(U), poly(dT), poly(C), poly(dA), but not by poly(G). Activity of helicase is dependent on magnesium.[10] [11] [12] The exoribonuclease acts on both ssRNA and dsRNA in a 3' to 5' direction.[13] [14] [15] Nsp7-nsp8 hexadecamer may possibly confer processivity to the polymerase, maybe by binding to dsRNA or by producing primers utilized by the latter.[16] [17] [18] Nsp9 is a ssRNA-binding protein.[19] [20] [21] NendoU is a Mn(2+)-dependent, uridylate-specific enzyme, which leaves 2'-3'-cyclic phosphates 5' to the cleaved bond.[22] [23] [24] 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 PubMedCoronavirus replication and transcription machinery involves multiple virus-encoded nonstructural proteins (nsp). We report the crystal structure of the hexadecameric nsp7-nsp8 supercomplex from the severe acute respiratory syndrome coronavirus at 2.4-angstroms resolution. nsp8 has a novel 'golf-club' fold with two conformations. The supercomplex is a unique hollow, cylinder-like structure assembled from eight copies of nsp8 and held tightly together by eight copies of nsp7. With an internal diameter of approximately 30 angstroms, the central channel has dimensions and positive electrostatic properties favorable for nucleic acid binding, implying that its role is to confer processivity on RNA-dependent RNA polymerase. Insights into SARS-CoV transcription and replication from the structure of the nsp7-nsp8 hexadecamer.,Zhai Y, Sun F, Li X, Pang H, Xu X, Bartlam M, Rao Z Nat Struct Mol Biol. 2005 Nov;12(11):980-6. PMID:16228002[25] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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