FEATURES

FAMILY

DESCRIPTION

Also known as PA_I57A0, PA. 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. Influenza RNA polymerase is composed of three subunits: PB1, PB2 and PA. Interacts (via C-terminus) with PB1 (via N-terminus).

EXTERNAL LINKS

PA

Polymerase acidic protein

PA

Molecular Synopsis