ID   PB2_INBP9               Reviewed;         770 AA.
AC   O36431;
DT   30-MAY-2000, integrated into UniProtKB/Swiss-Prot.
DT   01-JAN-1998, sequence version 1.
DT   03-AUG-2022, entry version 80.
DE   RecName: Full=Polymerase basic protein 2 {ECO:0000255|HAMAP-Rule:MF_04062};
DE   AltName: Full=RNA-directed RNA polymerase subunit P3 {ECO:0000255|HAMAP-Rule:MF_04062};
GN   Name=PB2 {ECO:0000255|HAMAP-Rule:MF_04062};
OS   Influenza B virus (strain B/Panama/45/1990).
OC   Viruses; Riboviria; Orthornavirae; Negarnaviricota; Polyploviricotina;
OC   Insthoviricetes; Articulavirales; Orthomyxoviridae; Betainfluenzavirus.
OX   NCBI_TaxID=408929;
OH   NCBI_TaxID=9606; Homo sapiens (Human).
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RX   PubMed=9281500; DOI=10.1006/viro.1997.8682;
RA   Jambrina E., Barcena J., Uez O., Portela A.;
RT   "The three subunits of the polymerase and the nucleoprotein of influenza B
RT   virus are the minimum set of viral proteins required for expression of a
RT   model RNA template.";
RL   Virology 235:209-217(1997).
CC   -!- FUNCTION: Plays an essential role in transcription initiation and cap-
CC       stealing mechanism, in which cellular capped pre-mRNAs are used to
CC       generate primers for viral transcription. Recognizes and binds a wide
CC       range of cap structures of target pre-RNAs which are subsequently
CC       cleaved after 10-13 nucleotides by the viral protein PA. Plays a role
CC       in the initiation of the viral genome replication and modulates the
CC       activity of the ribonucleoprotein (RNP) complex. {ECO:0000255|HAMAP-
CC       Rule:MF_04062}.
CC   -!- SUBUNIT: Influenza RNA polymerase is composed of three subunits: PB1,
CC       PB2 and PA. Interacts (via N-terminus) with PB1 (via C-terminus).
CC       Interacts with nucleoprotein NP (via N-terminus). {ECO:0000255|HAMAP-
CC       Rule:MF_04062}.
CC   -!- SUBCELLULAR LOCATION: Virion {ECO:0000255|HAMAP-Rule:MF_04062}. Host
CC       nucleus {ECO:0000255|HAMAP-Rule:MF_04062}.
CC   -!- SIMILARITY: Belongs to the influenza viruses PB2 family.
CC       {ECO:0000255|HAMAP-Rule:MF_04062}.
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DR   EMBL; AF005737; AAB72044.1; -; mRNA.
DR   PDB; 6QWL; EM; 4.10 A; Q=1-770.
DR   PDBsum; 6QWL; -.
DR   SMR; O36431; -.
DR   IntAct; O36431; 1.
DR   PRIDE; O36431; -.
DR   GO; GO:0042025; C:host cell nucleus; IEA:UniProtKB-SubCell.
DR   GO; GO:0044423; C:virion component; IEA:UniProtKB-UniRule.
DR   GO; GO:0003723; F:RNA binding; IEA:UniProtKB-UniRule.
DR   GO; GO:0003968; F:RNA-directed 5'-3' RNA polymerase activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0006370; P:7-methylguanosine mRNA capping; IEA:UniProtKB-UniRule.
DR   GO; GO:0075526; P:cap snatching; IEA:UniProtKB-UniRule.
DR   GO; GO:0039523; P:suppression by virus of host mRNA transcription via inhibition of 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:InterPro.
DR   Gene3D; 3.30.30.90; -; 1.
DR   HAMAP; MF_04062; INV_PB2; 1.
DR   InterPro; IPR001591; INV_PB2.
DR   InterPro; IPR037258; PDB2_C.
DR   Pfam; PF00604; Flu_PB2; 1.
DR   SUPFAM; SSF160453; SSF160453; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Cap snatching;
KW   Eukaryotic host gene expression shutoff by virus;
KW   Eukaryotic host transcription shutoff by virus;
KW   Host gene expression shutoff by virus; Host nucleus;
KW   Host-virus interaction; Inhibition of host RNA polymerase II by virus;
KW   mRNA capping; mRNA processing; Viral transcription; Virion.
FT   CHAIN           1..770
FT                   /note="Polymerase basic protein 2"
FT                   /id="PRO_0000078846"
FT   MOTIF           740..743
FT                   /note="Nuclear localization signal"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_04062"
SQ   SEQUENCE   770 AA;  87953 MW;  63216BCD2B8CD051 CRC64;
     MTLAKIELLK QLLRDNEAKT VLKQTTVDQY NIIRKFNTSR IEKNPSLRMK WAMCSNFPLA
     LTKGDMANRI PLEYKGIQLK TNAEDIGTKG QMCSIAAVTW WNTYGPIGDT EGFEKVYESF
     FLRKMRLDNA TWGRITFGPV ERVRKRVLLN PLTKEMPPDE ASNVIMEILF PKEAGIPRES
     TWIHRELIKE KREKLKGTMI TPIVLAYMLE RELVARRRFL PVAGATSAEF IEMLHCLQGE
     NWRQIYHPGG NKLTESRSQS MIVACRKIIR RSIVASNPLE LAVEIANKTV IDTEPLKSCL
     TAIDGGDVAC DIIRAALGLK IRQRQRFGRL ELKRISGRGF KNDEEILIGN GTIQKIGIWD
     GEEEFHVRCG ECRGILKKSK MRMEKLLINS AKKEDMKDLI ILCMVFSQDT RMFQGVRGEI
     NFLNRAGQLL SPMYQLQRYF LNRSNDLFDQ WGYEESPKAS ELHGINELMN ASDYTLKGVV
     VTKNVIDDFS STETEKVSIT KNLSLIKRTG EVIMGANDVS ELESQAQLMI TYDTPKMWEM
     GTTKELVQNT YQWVLKNLVT LKAQFLLGKE DMFQWDAFEA FESIIPQKMA GQYSGFARAV
     LKQMRDQEVM KTDQFIKLLP FCFSPPKLRS NGEPYQFLRL VLKGGGENFI EVRKGSPLFS
     YNPQTEVLTI CGRMMSLKGK IEDEERNRSM GNAVLAGFLV SGKYDPDLGD FKTIEELEKL
     KPGEKANILL YQGKPVKVVK RKRYSALSND ISQGIKRQRM TVESMGWALS