catalytic activity:Nucleoside triphosphate + RNA(n) = diphosphate + RNA(n+1).,function:DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Largest and catalytic core component of RNA polymerase I which synthesizes ribosomal RNA precursors. Forms the polymerase active center together with the second largest subunit. A single stranded DNA template strand of the promoter is positioned within the central active site cleft of Pol I. A bridging helix emanates from RPA1 and crosses the cleft near the catalytic site and is thought to promote translocation of Pol I by acting as a ratchet that moves the RNA-DNA hybrid through the active site by switching from straight to bent conformations at each step of nucleotide addition.,PTM:Phosphorylated.,similarity:Belongs to the RNA polymerase beta' chain family.,subunit:Component of the RNA polymerase I (Pol I) complex consisting of at least 13 subunits. Interacts with MYO1C.,
Nucleus, nucleolus . Chromosome .
Colon,Skin,Uterus,