4adp: Difference between revisions
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[[ | ==HCV-J6 NS5B POLYMERASE V405I MUTANT== | ||
<StructureSection load='4adp' size='340' side='right' caption='[[4adp]], [[Resolution|resolution]] 1.90Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[4adp]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Hepatitis_c_virus Hepatitis c virus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4ADP OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4ADP FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/RNA-directed_RNA_polymerase RNA-directed RNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.48 2.7.7.48] </span></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=4adp FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4adp OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4adp RCSB], [http://www.ebi.ac.uk/pdbsum/4adp PDBsum]</span></td></tr> | |||
<table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The hepatitis C virus (HCV) NS5B protein is an RNA-dependent RNA polymerase essential for replication of the viral RNA genome. In vitro and presumably in vivo, NS5B initiates RNA synthesis by a de novo mechanism and then processively copies the whole RNA template. Dissections of de novo RNA synthesis by genotype 1 NS5B proteins previously established that there are two successive crucial steps in de novo initiation. The first is dinucleotide formation, which requires a closed conformation, and the second is the transition to elongation, which requires an opening of NS5B. We also recently published a combined structural and functional analysis of genotype 2 HCV-NS5B proteins (of strains JFH1 and J6) that established residue 405 as a key element in de novo RNA synthesis (P. Simister et al., J. Virol. 83:11926-11939, 2009; M. Schmitt et al., J. Virol 85:2565-2581, 2011). We hypothesized that this residue stabilizes a particularly closed conformation conducive to dinucleotide formation. Here we report similar in vitro dissections of de novo synthesis for J6 and JFH1 NS5B proteins, as well as for mutants at position 405 of several genotype 1 and 2 strains. Our results show that an isoleucine at position 405 can promote both dinucleotide formation and the transition to elongation. New structural results highlight a molecular switch of position 405 with long-range effects, resolving the implied paradox of how the same residue can successively favor both the closed conformation of the dinucleotide formation step and the opening necessary to the transition step. | |||
Two crucial early steps in RNA synthesis by the hepatitis C virus polymerase involve a dual role of residue 405.,Scrima N, Caillet-Saguy C, Ventura M, Harrus D, Astier-Gin T, Bressanelli S J Virol. 2012 Jul;86(13):7107-17. Epub 2012 Apr 24. PMID:22532694<ref>PMID:22532694</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | |||
*[[RNA polymerase|RNA polymerase]] | |||
== | == References == | ||
[[ | <references/> | ||
__TOC__ | |||
== | </StructureSection> | ||
< | |||
[[Category: Hepatitis c virus]] | [[Category: Hepatitis c virus]] | ||
[[Category: RNA-directed RNA polymerase]] | [[Category: RNA-directed RNA polymerase]] | ||
Revision as of 10:18, 5 June 2014
HCV-J6 NS5B POLYMERASE V405I MUTANTHCV-J6 NS5B POLYMERASE V405I MUTANT
Structural highlights
Publication Abstract from PubMedThe hepatitis C virus (HCV) NS5B protein is an RNA-dependent RNA polymerase essential for replication of the viral RNA genome. In vitro and presumably in vivo, NS5B initiates RNA synthesis by a de novo mechanism and then processively copies the whole RNA template. Dissections of de novo RNA synthesis by genotype 1 NS5B proteins previously established that there are two successive crucial steps in de novo initiation. The first is dinucleotide formation, which requires a closed conformation, and the second is the transition to elongation, which requires an opening of NS5B. We also recently published a combined structural and functional analysis of genotype 2 HCV-NS5B proteins (of strains JFH1 and J6) that established residue 405 as a key element in de novo RNA synthesis (P. Simister et al., J. Virol. 83:11926-11939, 2009; M. Schmitt et al., J. Virol 85:2565-2581, 2011). We hypothesized that this residue stabilizes a particularly closed conformation conducive to dinucleotide formation. Here we report similar in vitro dissections of de novo synthesis for J6 and JFH1 NS5B proteins, as well as for mutants at position 405 of several genotype 1 and 2 strains. Our results show that an isoleucine at position 405 can promote both dinucleotide formation and the transition to elongation. New structural results highlight a molecular switch of position 405 with long-range effects, resolving the implied paradox of how the same residue can successively favor both the closed conformation of the dinucleotide formation step and the opening necessary to the transition step. Two crucial early steps in RNA synthesis by the hepatitis C virus polymerase involve a dual role of residue 405.,Scrima N, Caillet-Saguy C, Ventura M, Harrus D, Astier-Gin T, Bressanelli S J Virol. 2012 Jul;86(13):7107-17. Epub 2012 Apr 24. PMID:22532694[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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