POLR1B report

I. Expression across cell types

II. Expression across tissues

sc-RNAseq data

Insufficient scRNA-seq data for expression of POLR1B at tissue level.

III. Associated gene sets

GO_0014029Biological processneural crest formation
GO_0017126Biological processnucleologenesis
GO_0009303Biological processrRNA transcription
GO_0007566Biological processembryo implantation
GO_0006360Biological processtranscription by RNA polymerase I
GO_0005736Cellular componentRNA polymerase I complex
GO_0005694Cellular componentchromosome
GO_0005654Cellular componentnucleoplasm
GO_0005829Cellular componentcytosol
GO_0001650Cellular componentfibrillar center
GO_0003677Molecular functionDNA binding
GO_0071667Molecular functionDNA/RNA hybrid binding
GO_0032549Molecular functionribonucleoside binding
GO_0001054Molecular functionRNA polymerase I activity
GO_0005515Molecular functionprotein binding
GO_0008270Molecular functionzinc ion binding
GO_0003899Molecular functionDNA-directed 5'-3' RNA polymerase activity

IV. Literature review

[source]
Gene namePOLR1B
Protein nameDNA-directed RNA polymerase (EC 2.7.7.6)
RNA polymerase I subunit B
DNA-directed RNA polymerase I subunit RPA2 (EC 2.7.7.6)
DNA-directed RNA polymerase I subunit RPA2 (RNA polymerase I subunit 2) (EC 2.7.7.6) (DNA-directed RNA polymerase I 135 kDa polypeptide) (RPA135)
Synonyms
DescriptionFUNCTION: Catalytic core component of RNA polymerase I (Pol I), a DNA-dependent RNA polymerase which synthesizes ribosomal RNA precursors using the four ribonucleoside triphosphates as substrates. Transcribes 47S pre-rRNAs from multicopy rRNA gene clusters, giving rise to 5.8S, 18S and 28S ribosomal RNAs . Pol I-mediated transcription cycle proceeds through transcription initiation, transcription elongation and transcription termination stages. During transcription initiation, Pol I pre-initiation complex (PIC) is recruited by the selectivity factor 1 (SL1/TIF-IB) complex bound to the core promoter that precedes an rDNA repeat unit. The PIC assembly bends the promoter favoring the formation of the transcription bubble and promoter escape. Once the polymerase has escaped from the promoter it enters the elongation phase during which RNA is actively polymerized, based on complementarity with the template DNA strand. Highly processive, assembles in structures referred to as 'Miller trees' where many elongating Pol I complexes queue and transcribe the same rDNA coding regions. At terminator sequences downstream of the rDNA gene, PTRF interacts with Pol I and halts Pol I transcription leading to the release of the RNA transcript and polymerase from the DNA . Forms Pol I active center together with the largest subunit POLR1A/RPA1. Appends one nucleotide at a time to the 3' end of the nascent RNA, with POLR1A/RPA1 contributing a Mg(2+)-coordinating DxDGD motif, and POLR1B/RPA2 participating in the coordination of a second Mg(2+) ion and providing lysine residues believed to facilitate Watson-Crick base pairing between the incoming nucleotide and the template base. Typically, Mg(2+) ions direct a 5' nucleoside triphosphate to form a phosphodiester bond with the 3' hydroxyl of the preceding nucleotide of the nascent RNA, with the elimination of pyrophosphate. Has proofreading activity: Pauses and backtracks to allow the cleavage of a missincorporated nucleotide via POLR1H/RPA12. High Pol I processivity is associated with decreased transcription fidelity (By similarity). .

FUNCTION: 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. .

FUNCTION: 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. .

FUNCTION: 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. .

FUNCTION: 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. .

AccessionsENST00000417433.6 [Q9H9Y6-2]
C9JS83
ENST00000333990.10
F8WBB9
H7C0D9
Q4QRK8
ENST00000424062.1
C9JJG2
F8WAK7
F8WDS4
ENST00000430769.1
Q9BSR4
ENST00000458012.2
ENST00000263331.10 [Q9H9Y6-1]
Q9H9Y6
Q6DKI9
ENST00000448770.5
ENST00000537335.5 [Q9H9Y6-4]
ENST00000409894.7 [Q9H9Y6-5]
ENST00000541869.5 [Q9H9Y6-3]
ENST00000430293.1
F8WCS3
ENST00000438748.5