UniProt functional annotation for C3W5S0

UniProt code: C3W5S0.

Organism:		Influenza A virus (strain swl A/California/04/2009 H1N1).
Taxonomy:		Viruses; Riboviria; Orthornavirae; Negarnaviricota; Polyploviricotina; Insthoviricetes; Articulavirales; Orthomyxoviridae; Alphainfluenzavirus.
Function:		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. {ECO:0000256|HAMAP-Rule:MF_04063}.
Cofactor:		Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Evidence={ECO:0000256|HAMAP-Rule:MF_04063}; Note=Binds 2 manganese ions per subunit. {ECO:0000256|HAMAP- Rule:MF_04063};
Subunit:		Influenza RNA polymerase is composed of three subunits: PB1, PB2 and PA. {ECO:0000256|RuleBase:RU361280}.
Subunit:		Influenza RNA polymerase is composed of three subunits: PB1, PB2 and PA. Interacts (via C-terminus) with PB1 (via N-terminus). {ECO:0000256|ARBA:ARBA00011723, ECO:0000256|HAMAP-Rule:MF_04063}.
Subcellular location:		Host cytoplasm {ECO:0000256|HAMAP-Rule:MF_04063}. Host nucleus {ECO:0000256|HAMAP-Rule:MF_04063}. Note=PB1 and PA are transported in the host nucleus as a complex. {ECO:0000256|HAMAP- Rule:MF_04063}.
Ptm:		Phosphorylated on serines and threonines by host kinases, including human casein kinase II. {ECO:0000256|HAMAP-Rule:MF_04063}.
Similarity:		Belongs to the influenza viruses PA family. {ECO:0000256|HAMAP-Rule:MF_04063, ECO:0000256|RuleBase:RU361280}.
Similarity:		Belongs to the influenza viruses PA-X family. {ECO:0000256|ARBA:ARBA00008953}.

Annotations taken from UniProtKB at the EBI.