The cap-snatching endonuclease of influenza virus polymerase resides in the PA subunit

@article{Dias2009TheCE,
  title={The cap-snatching endonuclease of influenza virus polymerase resides in the PA subunit},
  author={Alexandre Dias and Denis Bouvier and Thibaut Cr{\'e}pin and Andrew A. McCarthy and Darren J Hart and Florence Baudin and Stephen Cusack and Rob W. H. Ruigrok},
  journal={Nature},
  year={2009},
  volume={458},
  pages={914-918}
}
The influenza virus polymerase, a heterotrimer composed of three subunits, PA, PB1 and PB2, is responsible for replication and transcription of the eight separate segments of the viral RNA genome in the nuclei of infected cells. The polymerase synthesizes viral messenger RNAs using short capped primers derived from cellular transcripts by a unique 'cap-snatching' mechanism. The PB2 subunit binds the 5′ cap of host pre-mRNAs, which are subsequently cleaved after 10–13 nucleotides by the viral… 

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