POLR1B DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Second largest core component of RNA polymerase I which synthesizes ribosomal RNA precursors. Proposed to contribute to the polymerase catalytic activity and forms the polymerase active center together with the largest subunit. Pol I is composed of mobile elements and RPA2 is part of the core element with the central large cleft and probably a clamp element that moves to open and close the cleft. Belongs to the RNA polymerase beta chain family. 5 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: EC 2.7.7.6; Nucleolus; Nucleotide Metabolism - purine; Nucleotide Metabolism - pyrimidine; Transcription initiation complex; Transferase
Chromosomal Location of human Ortholog: 2q14.1
Cellular Component:  chromosome; cytosol; fibrillar center; nucleoplasm; RNA polymerase I complex
Molecular Function:  DNA binding; metal ion binding; protein binding; ribonucleoside binding; RNA polymerase I activity
Biological Process:  embryo implantation; neural crest formation; nucleologenesis; rRNA transcription; transcription by RNA polymerase I
Disease: Treacher Collins Syndrome 4
Reference #:  Q9H9Y6 (UniProtKB)
Alt. Names/Synonyms: A135; DNA-directed RNA polymerase I 135 kDa polypeptide; DNA-directed RNA polymerase I 135kDa polypeptide; DNA-directed RNA polymerase I subunit RPA2; FLJ10816; FLJ21921; MGC131780; POLR1B; polymerase (RNA) I polypeptide B, 128kDa; polymerase (RNA) I subunit B; RNA polymerase I subunit 2; RNA polymerase I subunit B; RPA135; RPA2; Rpo1-2; TCS4
Gene Symbols: POLR1B
Molecular weight: 128,229 Da
Basal Isoelectric point: 8.07  Predict pI for various phosphorylation states
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POLR1B

Protein Structure Not Found.


Cross-references to other databases:  AlphaFold  |  STRING  |  cBioPortal  |  Wikipedia  |  Reactome  |  neXtProt  |  Protein Atlas  |  BioGPS  |  Pfam  |  RCSB PDB  |  ENZYME  |  Phospho.ELM  |  NetworKIN  |  GeneCards  |  UniProtKB  |  Entrez-Gene  |  GenPept  |  Ensembl Gene  |  Ensembl Protein