View source for 8rmr


==Influenza polymerase A/H7N9-4M replication complex, an asymmetric polymerase dimer bound to human ANP32A==
<StructureSection load='8rmr' size='340' side='right'caption='[[8rmr]], [[Resolution|resolution]] 3.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8rmr]] is a 7 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Influenza_A_virus_(A/Zhejiang/DTID-ZJU01/2013(H7N9)) Influenza A virus (A/Zhejiang/DTID-ZJU01/2013(H7N9))]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8RMR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8RMR 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]] 3.25&#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=8rmr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8rmr OCA], [https://pdbe.org/8rmr PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8rmr RCSB], [https://www.ebi.ac.uk/pdbsum/8rmr PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8rmr ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/M9TI86_9INFA M9TI86_9INFA] Plays an essential role in viral RNA transcription and replication by forming the heterotrimeric polymerase complex together with PB1 and PB2 subunits. The complex transcribes viral mRNAs by using a unique mechanism called cap-snatching. It consists in the hijacking and cleavage of host capped pre-mRNAs. These short capped RNAs are then used as primers for viral mRNAs. The PB2 subunit is responsible for the binding of the 5' cap of cellular pre-mRNAs which are subsequently cleaved after 10-13 nucleotides by the PA subunit that carries the endonuclease activity.[HAMAP-Rule:MF_04063][SAAS:SAAS00956500]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Replication of influenza viral RNA depends on at least two viral polymerases, a parental replicase and an encapsidase, and cellular factor ANP32. ANP32 comprises an LRR domain and a long C-terminal low complexity acidic region (LCAR). Here we present evidence suggesting that ANP32 is recruited to the replication complex as an electrostatic chaperone that stabilises the encapsidase moiety within apo-polymerase symmetric dimers that are distinct for influenza A and B polymerases. The ANP32 bound encapsidase, then forms the asymmetric replication complex with the replicase, which is embedded in a parental ribonucleoprotein particle (RNP). Cryo-EM structures reveal the architecture of the influenza A and B replication complexes and the likely trajectory of the nascent RNA product into the encapsidase. The cryo-EM map of the FluB replication complex shows extra density attributable to the ANP32 LCAR wrapping around and stabilising the apo-encapsidase conformation. These structures give new insight into the various mutations that adapt avian strain polymerases to use the distinct ANP32 in mammalian cells.

Structures of influenza A and B replication complexes give insight into avian to human host adaptation and reveal a role of ANP32 as an electrostatic chaperone for the apo-polymerase.,Arragain B, Krischuns T, Pelosse M, Drncova P, Blackledge M, Naffakh N, Cusack S Nat Commun. 2024 Aug 19;15(1):6910. doi: 10.1038/s41467-024-51007-3. PMID:39160148<ref>PMID:39160148</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
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== References ==
<references/>
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</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Arragain B]]
[[Category: Cusack S]]