Article · Wikipedia archive · Last revised Jul 9, 2026

Polymerase basic protein 2

Influenza virus polymerase basic protein 2 (PB2) is a core subunit of the viral RNA-dependent RNA polymerase complex that is essential for both transcription and replication of the negative-strand RNA genome. PB2 binds capped host pre-mRNAs and participates in the “cap snatching” process that generates primers for viral mRNA synthesis. PB2 also acts as a key determinant of host range and pathogenicity in different influenza A strains, including through amino-acid substitutions such as the lysine at position 627. In addition, PB2 is imported into the mitochondrial matrix, where it may influence viral replication and host–virus interactions.

Last revised
Jul 9, 2026
Read time
≈ 1 min
Length
296 w
Citations
6
Source
Wikipedia ↗
Identifiers
OrganismInfluenza A virus
SymbolPB2
Entrez956536
PDB2VQZ
RefSeq (Prot)NP_040987.1
UniProtP21428
Other data
ChromosomeGenome: 0 - 0 Mb
Search for
StructuresSwiss-model
DomainsInterPro

Influenza virus polymerase basic protein 2 (PB2) is a core subunit of the viral RNA-dependent RNA polymerase complex that is essential for both transcription and replication of the negative-strand RNA genome.12 PB2 binds capped host pre-mRNAs and participates in the “cap snatching” process that generates primers for viral mRNA synthesis.3 PB2 also acts as a key determinant of host range and pathogenicity in different influenza A strains, including through amino-acid substitutions such as the lysine at position 627.45 In addition, PB2 is imported into the mitochondrial matrix, where it may influence viral replication and host–virus interactions.6

References

References

  1. "Polymerase basic protein 2". UniProt. P21428.
  2. Te Velthuis AJ, Fodor E (August 2016). "Influenza virus RNA polymerase: insights into the mechanisms of viral RNA synthesis". Nature Reviews. Microbiology. 14 (8): 479–93. doi:10.1038/nrmicro.2016.87. PMC 4966622. PMID 27396566.
  3. Bouvier NM, Palese P (September 2008). "The biology of influenza viruses". Vaccine. 26 (Suppl 4): D49–D53. doi:10.1016/j.vaccine.2008.07.039. PMC 3074182. PMID 19230160.
  4. Kuzuhara T, Kise D, Yoshida H, Horita T, Murazaki Y, Nishimura A, et al. (March 2009). "Structural basis of the influenza A virus RNA polymerase PB2 RNA-binding domain containing the pathogenicity-determinant lysine 627 residue". The Journal of Biological Chemistry. 284 (11): 6855–6860. doi:10.1074/jbc.C800224200. PMC 2652293. PMID 19144639.
  5. Graef KM, Vreede FT, Lau YF, McCall AW, Carr SM, Subbarao K, et al. (September 2010). "The PB2 subunit of the influenza virus RNA polymerase affects virulence by interacting with the mitochondrial antiviral signaling protein and inhibiting expression of beta interferon". Journal of Virology. 84 (17): 8433–45. doi:10.1128/JVI.00879-10. PMC 2919034. PMID 20538852.
  6. Long JC, Fodor E (October 2016). "The PB2 Subunit of the Influenza A Virus RNA Polymerase Is Imported into the Mitochondrial Matrix". Journal of Virology. 90 (19): 8729–8738. doi:10.1128/JVI.01384-16. PMC 5021425. PMID 27440905.