View source for 9dus


==Cryo-EM structure of the Measles Virus polymerase (L) protein in complex with the tetrameric phosphoprotein (P)==
<StructureSection load='9dus' size='340' side='right'caption='[[9dus]], [[Resolution|resolution]] 3.12&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9dus]] is a 5 chain structure with sequence from [https://en.wikipedia.org/wiki/Measles_virus_strain_Edmonston-B Measles virus strain Edmonston-B]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9DUS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9DUS FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.12&#8491;</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=9dus FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9dus OCA], [https://pdbe.org/9dus PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9dus RCSB], [https://www.ebi.ac.uk/pdbsum/9dus PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9dus ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q83626_MEASF Q83626_MEASF] RNA-directed RNA polymerase that catalyzes the replication of viral genomic RNA. The template is composed of the viral RNA tightly encapsidated by the nucleoprotein (N). The replicase mode is dependent on intracellular N protein concentration. In this mode, the polymerase replicates the whole viral genome without recognizing transcriptional signals, and the replicated genome is not caped or polyadenylated.[ARBA:ARBA00003132][PIRNR:PIRNR000830]  RNA-directed RNA polymerase that catalyzes the transcription of viral mRNAs, their capping and polyadenylation. The template is composed of the viral RNA tightly encapsidated by the nucleoprotein (N). The viral polymerase binds to the genomic RNA at the 3' leader promoter, and transcribes subsequently all viral mRNAs with a decreasing efficiency. The first gene is the most transcribed, and the last the least transcribed. The viral phosphoprotein acts as a processivity factor. Capping is concomitant with initiation of mRNA transcription. Indeed, a GDP polyribonucleotidyl transferase (PRNTase) adds the cap structure when the nascent RNA chain length has reached few nucleotides. Ribose 2'-O methylation of viral mRNA cap precedes and facilitates subsequent guanine-N-7 methylation, both activities being carried by the viral polymerase. Polyadenylation of mRNAs occur by a stuttering mechanism at a slipery stop site present at the end viral genes. After finishing transcription of a mRNA, the polymerase can resume transcription of the downstream gene.[PIRNR:PIRNR000830]
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</StructureSection>
[[Category: Large Structures]]
[[Category: Measles virus strain Edmonston-B]]
[[Category: Liu B]]
[[Category: Wang D]]
[[Category: Yang G]]