ID Q1K9G5_INBAA Unreviewed; 752 AA. AC Q1K9G5; DT 30-MAY-2006, integrated into UniProtKB/TrEMBL. DT 30-MAY-2006, sequence version 1. DT 28-FEB-2018, entry version 46. DE RecName: Full=RNA-directed RNA polymerase catalytic subunit {ECO:0000256|RuleBase:RU004330, ECO:0000256|SAAS:SAAS00997580}; DE EC=2.7.7.48 {ECO:0000256|RuleBase:RU004330, ECO:0000256|SAAS:SAAS00997646}; GN Name=PB1 {ECO:0000256|HAMAP-Rule:MF_04065, GN ECO:0000313|EMBL:ABF21251.1}; OS Influenza B virus (strain B/Ann Arbor/1/1986). OC Viruses; ssRNA viruses; ssRNA negative-strand viruses; OC Orthomyxoviridae; Influenzavirus B. OX NCBI_TaxID=11521 {ECO:0000313|EMBL:ABF21251.1, ECO:0000313|Proteomes:UP000160484}; OH NCBI_TaxID=9606; Homo sapiens (Human). RN [1] {ECO:0000313|EMBL:ABF21251.1, ECO:0000313|Proteomes:UP000160484} RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=B/Ann Arbor/1/1986 {ECO:0000313|EMBL:ABF21251.1}; RA Mbawuike I.N., Zhang Y., Yamada R.E., Nino D., Bui H.-H., Sette A., RA Couch R.B.; RT "Complete Genome Sequencing And Analysis Of Selected Influenza Virus RT Vaccine Strains Spanning Six Decades (1933-1999)."; RL Submitted (APR-2006) to the EMBL/GenBank/DDBJ databases. CC -!- FUNCTION: RNA-dependent RNA polymerase which is responsible for CC replication and transcription of virus RNA segments. The CC transcription of viral mRNAs occurs by a unique mechanism called CC cap-snatching. 5' methylated caps of cellular mRNAs are cleaved CC after 10-13 nucleotides by PA. In turn, these short capped RNAs CC are used as primers by PB1 for transcription of viral mRNAs. CC During virus replication, PB1 initiates RNA synthesis and copies CC vRNA into complementary RNA (cRNA) which in turn serves as a CC template for the production of more vRNAs. {ECO:0000256|HAMAP- CC Rule:MF_04065}. CC -!- CATALYTIC ACTIVITY: Nucleoside triphosphate + RNA(n) = diphosphate CC + RNA(n+1). {ECO:0000256|RuleBase:RU004330, CC ECO:0000256|SAAS:SAAS00605060}. CC -!- SUBUNIT: Influenza RNA polymerase is composed of three subunits: CC PB1, PB2 and PA. Interacts (via N-terminus) with PA (via C- CC terminus). Interacts (via C-terminus) with PB2 (via N-terminus); CC this interaction is essential for transcription initiation. CC {ECO:0000256|HAMAP-Rule:MF_04065}. CC -!- SUBCELLULAR LOCATION: Host nucleus {ECO:0000256|HAMAP- CC Rule:MF_04065}. Host cytoplasm {ECO:0000256|HAMAP-Rule:MF_04065}. CC -!- PTM: Phosphorylated by host PRKCA. {ECO:0000256|HAMAP- CC Rule:MF_04065}. CC -!- SIMILARITY: Belongs to the influenza viruses polymerase PB1 CC family. {ECO:0000256|HAMAP-Rule:MF_04065, CC ECO:0000256|SAAS:SAAS00997533}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; DQ508911; ABF21251.1; -; Genomic_RNA. DR Proteomes; UP000160484; Genome. DR GO; GO:0030430; C:host cell cytoplasm; IEA:UniProtKB-SubCell. DR GO; GO:0042025; C:host cell nucleus; IEA:UniProtKB-SubCell. DR GO; GO:0000166; F:nucleotide binding; IEA:UniProtKB-UniRule. DR GO; GO:0003723; F:RNA binding; IEA:InterPro. DR GO; GO:0003968; F:RNA-directed 5'-3' RNA polymerase activity; IEA:UniProtKB-UniRule. DR GO; GO:0039523; P:suppression by virus of host RNA polymerase II activity; IEA:UniProtKB-UniRule. DR GO; GO:0006351; P:transcription, DNA-templated; IEA:UniProtKB-UniRule. DR GO; GO:0039694; P:viral RNA genome replication; IEA:UniProtKB-UniRule. DR GO; GO:0019083; P:viral transcription; IEA:UniProtKB-KW. DR HAMAP; MF_04065; INFV_RDRP; 1. DR InterPro; IPR007099; RNA-dir_pol_NSvirus. DR InterPro; IPR001407; RNA_pol_PB1_influenza. DR Pfam; PF00602; Flu_PB1; 1. DR PIRSF; PIRSF000827; RdRPol_OMV; 1. DR PROSITE; PS50525; RDRP_SSRNA_NEG_SEG; 1. PE 3: Inferred from homology; KW Complete proteome {ECO:0000313|Proteomes:UP000160484}; KW Eukaryotic host gene expression shutoff by virus {ECO:0000256|HAMAP- KW Rule:MF_04065}; KW Eukaryotic host transcription shutoff by virus {ECO:0000256|HAMAP- KW Rule:MF_04065}; Host cytoplasm {ECO:0000256|HAMAP-Rule:MF_04065}; KW Host gene expression shutoff by virus {ECO:0000256|HAMAP- KW Rule:MF_04065}; Host nucleus {ECO:0000256|HAMAP-Rule:MF_04065}; KW Host-virus interaction {ECO:0000256|HAMAP-Rule:MF_04065}; KW Inhibition of host RNA polymerase II by virus {ECO:0000256|HAMAP- KW Rule:MF_04065}; KW Nucleotide-binding {ECO:0000256|HAMAP-Rule:MF_04065, KW ECO:0000256|SAAS:SAAS00605058}; KW Nucleotidyltransferase {ECO:0000256|HAMAP-Rule:MF_04065, KW ECO:0000256|SAAS:SAAS00605055}; KW Phosphoprotein {ECO:0000256|HAMAP-Rule:MF_04065}; KW RNA-directed RNA polymerase {ECO:0000256|RuleBase:RU004330, KW ECO:0000256|SAAS:SAAS00605053}; KW Transferase {ECO:0000256|HAMAP-Rule:MF_04065, KW ECO:0000256|SAAS:SAAS00605061}; KW Viral RNA replication {ECO:0000256|HAMAP-Rule:MF_04065, KW ECO:0000256|SAAS:SAAS00605045}; KW Viral transcription {ECO:0000256|HAMAP-Rule:MF_04065}. FT DOMAIN 286 482 RdRp catalytic. {ECO:0000259|PROSITE: FT PS50525}. FT REGION 249 256 Promoter-binding site. FT {ECO:0000256|HAMAP-Rule:MF_04065}. FT MOTIF 187 195 Nuclear localization signal. FT {ECO:0000256|HAMAP-Rule:MF_04065}. FT MOTIF 203 216 Nuclear localization signal. FT {ECO:0000256|HAMAP-Rule:MF_04065}. SQ SEQUENCE 752 AA; 84351 MW; B136FCBB96BB640A CRC64; MNINPYFLFI DVPIQAAIST TFPYTGVPPY SHGTGTGYTI DTVIRTHEYS NKGKQYISDV TGCTMIDPTN GPLPEDNEPS AYAQLDCVLE ALDRMDEEHP GLFQAASQNA MEALMVTTVD KLTQGRQTFD WTVCRNQPAA TALNTTITSF RLNDLNGADK GGLVPFCQDI IDSLDRPEMT FFSVKNIKKK LPAKNRKGFL IKRIPMKVKD RITRVEYIKR ALSLNTMTKD AERGKLKRRA IATAGIQIRG FVLVVENLAK NICENLEQSG LPVGGNEKKA KLSNAVAKML SNCPPGGISM TVTGDNTKWN ECLNPRIFLA MTERITRDSP IWFRDFCSIA PVLFSNKIAR LGKGFMITSK TKRLKAQIPC PDLFSIPLER YNEETRAKLK KLKPFFNEEG TASLSPGMMM GMFNMLSTVL GVAALGIKNI GNKEYLWDGL QSSDDFALFV NAKDEETCME GINDFYRTCK LLGINMSKKK SYCNETGMFE FTSMFYRDGF VSNFAMELPS FGVAGVNESA DMAIGMTIIK NNMINNGMGP ATAQTAIQLF IADYRYTYKC HRGDSKVEGK RMKIIKELWE NTKGRDGLLV ADGGPNIYNL RNLHIPEIVL KYNLMDPEYK GRLLHPQNPF VGHLSIEGIK EADITPAHGP VKKMDYDAVS GTHSWRTKRN RSILNTDQRN MILEEQCYAK CCNLFEACFN SASYRKPVGQ HSMLEAMAHR LRMDARLDYE SGRMSKDDFE KAMAHLGEIG YI //