ID   PB2_I56A1               Reviewed;         759 AA.
AC   Q20P12;
DT   06-MAR-2007, integrated into UniProtKB/Swiss-Prot.
DT   18-APR-2006, sequence version 1.
DT   03-AUG-2022, entry version 69.
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 A virus (strain A/Duck/Czechoslovakia/1956 H4N6).
OC   Viruses; Riboviria; Orthornavirae; Negarnaviricota; Polyploviricotina;
OC   Insthoviricetes; Articulavirales; Orthomyxoviridae; Alphainfluenzavirus.
OX   NCBI_TaxID=385590;
OH   NCBI_TaxID=8782; Aves.
OH   NCBI_TaxID=9823; Sus scrofa (Pig).
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC RNA].
RX   PubMed=16439620; DOI=10.1126/science.1121586;
RA   Obenauer J.C., Denson J., Mehta P.K., Su X., Mukatira S., Finkelstein D.B.,
RA   Xu X., Wang J., Ma J., Fan Y., Rakestraw K.M., Webster R.G., Hoffmann E.,
RA   Krauss S., Zheng J., Zhang Z., Naeve C.W.;
RT   "Large-scale sequence analysis of avian influenza isolates.";
RL   Science 311:1576-1580(2006).
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 the 7-
CC       methylguanosine-containing cap of the target pre-RNA which is
CC       subsequently cleaved after 10-13 nucleotides by the viral protein PA.
CC       Plays a role in the initiation of the viral genome replication and
CC       modulates the activity of the ribonucleoprotein (RNP) complex.
CC       {ECO:0000255|HAMAP-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; CY005822; ABB90230.1; -; Genomic_RNA.
DR   SMR; Q20P12; -.
DR   PRO; PR:Q20P12; -.
DR   Proteomes; UP000008434; Genome.
DR   Proteomes; UP000108613; Genome.
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   3: Inferred from homology;
KW   Cap snatching; 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..759
FT                   /note="Polymerase basic protein 2"
FT                   /id="PRO_0000279626"
FT   MOTIF           736..739
FT                   /note="Nuclear localization signal"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_04062"
FT   SITE            627
FT                   /note="Avian adaptation"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_04062"
SQ   SEQUENCE   759 AA;  85874 MW;  ECDE248C014940A1 CRC64;
     MERIKELRDL LSQSRTREIL TKTTVDHMAI IKKYTSGRQE KNPALRMKWM MAMKYPITAD
     KRIMEMIPER NEQGQTLWSK TNDAGSDRVM VSPLAVTWWN RNGPATSTVH YPKVYKTYFE
     KVERLKHGTF GPVHFRNQVK IRRRVDINPG HADLSAKEAQ DVIMEVVFPN EVGARILTSE
     SQLTITKEKK EELQDCKIAP LMVAYMLERE LVRKTRFLPV AGGTSSVYIE VLHLTQGTCW
     EQMYTPGGEV RNDDVDQSLI IAARNIVRRA TVSADPLASL LEMCHSTQIG GIRMVDILRQ
     NPTEEQAVDI CKAAMGLRIS SSFSFGGFTF KRTSGSSVKR EEEVLTGNLQ TLKIRVHEGY
     EEFTMVGRRA TAILRKATRR LIQLIVSGRD EQSIAEAIIV AMVFSQEDCM IKAVRGDLNF
     VNRANQRLNP MHQLLRHFQK DAKVLFQNWG IEPIDNVMGM IGILPDMTPS TEMSLRGLRV
     SKMGVDEYSS TERVVVSIDR FLRVRDQRGN VLLSPEEVSE TQGTEKLTIT YSSSMMWEIN
     GPESVLVNTY QWIIRNWETV KIQWSQDPTM LYNKMEFEPF QSLVPKAARG QYSGFVRTLF
     QQMRDVLGTF DTVQIIKLLP FAAAPPEQSR MQFSSLTVNV RGSGMRILVR GNSPVFNYNK
     ATKRLTVLGK DAGALTEDPD EGTAGVESAV LRGFLILGKE DKRYGPALSI NELSNLAKGE
     KANVLIGQGD VVLVMKRKRD SSILTDSQTA TKRIRMAIN