8rn0

From Proteopedia

Influenza polymerase A/H7N9-4M encapsidase plus 627(R) / human ANP32A (from "Influenza polymerase A/H7N9-4M replication complex" | Local refinement)

Structural highlights

8rn0 is a 5 chain structure with sequence from Homo sapiens and Influenza A virus (A/Zhejiang/DTID-ZJU01/2013(H7N9)). Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Electron Microscopy, Resolution 3.13Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

X5F427_9INFA Plays an essential role in transcription initiation and cap-stealing mechanism, in which cellular capped pre-mRNAs are used to generate primers for viral transcription. Recognizes and binds the 7-methylguanosine-containing cap of the target pre-RNA which is subsequently cleaved after 10-13 nucleotides by the viral protein PA. Plays a role in the initiation of the viral genome replication and modulates the activity of the ribonucleoprotein (RNP) complex.[HAMAP-Rule:MF_04062][SAAS:SAAS01109044]

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^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Arragain B, Krischuns T, Pelosse M, Drncova P, Blackledge M, Naffakh N, Cusack S. 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. Nat Commun. 2024 Aug 19;15(1):6910. PMID:39160148 doi:10.1038/s41467-024-51007-3