RPB1_EUPOC
ID RPB1_EUPOC Reviewed; 478 AA.
AC P28364;
DT 01-DEC-1992, integrated into UniProtKB/Swiss-Prot.
DT 01-DEC-1992, sequence version 1.
DT 03-AUG-2022, entry version 87.
DE RecName: Full=DNA-directed RNA polymerase II subunit RPB1;
DE Short=RNA polymerase II subunit B1;
DE EC=2.7.7.6;
DE AltName: Full=DNA-directed RNA polymerase III largest subunit;
DE Flags: Fragment;
GN Name=RPB1;
OS Euplotoides octocarinatus (Freshwater ciliate) (Euplotes octocarinatus).
OC Eukaryota; Sar; Alveolata; Ciliophora; Intramacronucleata; Spirotrichea;
OC Hypotrichia; Euplotida; Euplotidae; Euplotes.
OX NCBI_TaxID=2716877;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC STRAIN=(68)-VIII;
RX PubMed=1408746; DOI=10.1093/nar/20.17.4445;
RA Kaufmann J., Klein A.;
RT "Gene dosage as a possible major determinant for equal expression levels of
RT genes encoding RNA polymerase subunits in the hypotrichous ciliate Euplotes
RT octocarinatus.";
RL Nucleic Acids Res. 20:4445-4450(1992).
RN [2]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-124.
RX PubMed=1461731; DOI=10.1093/nar/20.22.5985;
RA Kaufmann J., Florian V., Klein A.;
RT "TGA cysteine codons and intron sequences in conserved and nonconserved
RT positions are found in macronuclear RNA polymerase genes of Euplotes
RT octocarinatus.";
RL Nucleic Acids Res. 20:5985-5989(1992).
CC -!- FUNCTION: DNA-dependent RNA polymerase catalyzes the transcription of
CC DNA into RNA using the four ribonucleoside triphosphates as substrates.
CC Largest and catalytic component of RNA polymerase II which synthesizes
CC mRNA precursors and many functional non-coding RNAs. Forms the
CC polymerase active center together with the second largest subunit. Pol
CC II is the central component of the basal RNA polymerase II
CC transcription machinery. It is composed of mobile elements that move
CC relative to each other. RPB1 is part of the core element with the
CC central large cleft, the clamp element that moves to open and close the
CC cleft and the jaws that are thought to grab the incoming DNA template.
CC At the start of transcription, a single-stranded DNA template strand of
CC the promoter is positioned within the central active site cleft of Pol
CC II. A bridging helix emanates from RPB1 and crosses the cleft near the
CC catalytic site and is thought to promote translocation of Pol II by
CC acting as a ratchet that moves the RNA-DNA hybrid through the active
CC site by switching from straight to bent conformations at each step of
CC nucleotide addition. During transcription elongation, Pol II moves on
CC the template as the transcript elongates. Elongation is influenced by
CC the phosphorylation status of the C-terminal domain (CTD) of Pol II
CC largest subunit (RPB1), which serves as a platform for assembly of
CC factors that regulate transcription initiation, elongation, termination
CC and mRNA processing (By similarity). {ECO:0000250}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=a ribonucleoside 5'-triphosphate + RNA(n) = diphosphate +
CC RNA(n+1); Xref=Rhea:RHEA:21248, Rhea:RHEA-COMP:14527, Rhea:RHEA-
CC COMP:17342, ChEBI:CHEBI:33019, ChEBI:CHEBI:61557, ChEBI:CHEBI:140395;
CC EC=2.7.7.6;
CC -!- SUBUNIT: Component of the RNA polymerase II (Pol II) complex consisting
CC of 12 subunits. {ECO:0000250}.
CC -!- SUBCELLULAR LOCATION: Nucleus {ECO:0000250}.
CC -!- PTM: Phosphorylation activates POL II.
CC -!- MISCELLANEOUS: The binding of ribonucleoside triphosphate to the RNA
CC polymerase II transcribing complex probably involves a two-step
CC mechanism. The initial binding seems to occur at the entry (E) site and
CC involves a magnesium ion temporarily coordinated by three conserved
CC aspartate residues of the two largest RNA Pol II subunits. The
CC ribonucleoside triphosphate is transferred by a rotation to the
CC nucleotide addition (A) site for pairing with the template DNA. The
CC catalytic A site involves three conserved aspartate residues of the RNA
CC Pol II largest subunit which permanently coordinate a second magnesium
CC ion.
CC -!- SIMILARITY: Belongs to the RNA polymerase beta' chain family.
CC {ECO:0000305}.
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DR EMBL; X66452; CAA47068.1; -; Genomic_DNA.
DR PIR; S33886; S33886.
DR AlphaFoldDB; P28364; -.
DR SMR; P28364; -.
DR PRIDE; P28364; -.
DR GO; GO:0000428; C:DNA-directed RNA polymerase complex; IEA:UniProtKB-KW.
DR GO; GO:0005634; C:nucleus; IEA:UniProtKB-SubCell.
DR GO; GO:0003677; F:DNA binding; IEA:UniProtKB-KW.
DR GO; GO:0003899; F:DNA-directed 5'-3' RNA polymerase activity; IEA:UniProtKB-EC.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR GO; GO:0006351; P:transcription, DNA-templated; IEA:InterPro.
DR Gene3D; 4.10.860.120; -; 1.
DR InterPro; IPR045867; DNA-dir_RpoC_beta_prime.
DR InterPro; IPR000722; RNA_pol_asu.
DR InterPro; IPR006592; RNA_pol_N.
DR InterPro; IPR007080; RNA_pol_Rpb1_1.
DR InterPro; IPR044893; RNA_pol_Rpb1_clamp_domain.
DR PANTHER; PTHR19376; PTHR19376; 1.
DR Pfam; PF04997; RNA_pol_Rpb1_1; 1.
DR Pfam; PF00623; RNA_pol_Rpb1_2; 1.
DR SMART; SM00663; RPOLA_N; 1.
PE 3: Inferred from homology;
KW DNA-binding; DNA-directed RNA polymerase; Magnesium; Metal-binding;
KW Nucleotidyltransferase; Nucleus; Repeat; Transcription; Transferase; Zinc.
FT CHAIN 1..>478
FT /note="DNA-directed RNA polymerase II subunit RPB1"
FT /id="PRO_0000073939"
FT BINDING 68
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000250"
FT BINDING 71
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000250"
FT BINDING 78
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000250"
FT BINDING 81
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000250"
FT BINDING 474
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000250"
FT BINDING 474
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /ligand_note="ligand shared with RPB2"
FT /evidence="ECO:0000250"
FT BINDING 476
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000250"
FT BINDING 476
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /ligand_note="ligand shared with RPB2"
FT /evidence="ECO:0000250"
FT NON_TER 478
SQ SEQUENCE 478 AA; 54026 MW; 47A1ADD6ED98EB3D CRC64;
MSRGTIYTES TMDFQKVRKI QFGLLDPKEI QAMSVVQVEN EKIYDNGIPT DGGINDLRMG
TMEKAMRCST CQGDSKECPG HFGHIELAQP VFHIGFIDLV KKILKCVCFN CNKLLITDKH
DKYSALKRVK DPKLKLNKVY KVCKDIKVCG KADRKSETYT EGSGQKQPRL RKTGLKIKAE
FPIDEDDPST NDNKRDLSAS ECLKILGRIS PDDCKFLGFD MVLARPEWLI ISRLPVAPPP
VRPSVCMGSN IRQEDDLTHQ YQQILKANNQ LRKHLSTANH IINENYQLLQ FYCATLIDNE
QAGQMVSRHK SGGKAIKAIR ARLKGKEGRL RGNLMGKRVD FSARTVITCD PTLDLDQLGV
PRSIAENITI PEVVTPQNID EMRKLVINGP NKWPGAKYIK GEGGKMIDLS YAKTTETFID
YGYVIERHLK NDDFVLFNRQ PSLHKMSIMG HRVKVLPYST FRLNLSVTAP YNADFDGS
