RPA49, DNA-directed RNA polymerase I subunit RPA49
Also Known as
RPA49_YEAST, RPA49, RRN13
DNA-dependent RNA polymerases catalyze the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase I (Pol I) which synthesizes ribosomal RNA precursors. Besides, RNA polymerase I has intrinsic RNA cleavage activity. The heterodimer formed by RPA34 and RPA49 stimulates transcript elongation by Pol I. Subunit RPA49 can bind both single-stranded and double-stranded DNA. Component of the RNA polymerase I (Pol I) complex consisting of 14 subunits: RPA135, RPA190, RPC40, RPA14, RPB5, RPO26, RPA43, RPB8, RPA12, RPB10, RPC19, RPC10, RPA49 and RPA34. The complex is composed of a horseshoe-shaped core containing ten subunits (RPA135, RPA190, RPB5, RPO26, RPB8, RPB10, RPC10, RPA12, RPC19 and RPC40) where RPA135 and RPA190 form the DNA-binding cleft. Outside of the core, RPA14 and RPA43 form the stalk that mediates interactions with transcription initiation factors and newly synthesized RNA. Forms a TFIIF-like heterodimer with RPA34; the heterodimer formed by RPA34 and RPA49 can be dissociated from the Pol I core giving rise to a 12 subunit form A* of Pol I (formerly called pol A) that shows impaired transcript elongation activity and increased sensitivity to alpha-amanitin. The heterodimer formed by RPA34 and RPA49 stabilizes subunit RPA12 and stimulates RPA12-dependent RNA cleavage.