DNA-dependent RNA polymerases catalyze the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common core component of RNA polymerases I and III which synthesize ribosomal RNA precursors and small RNAs, such as 5S rRNA and tRNAs, respectively. Component of the RNA polymerase I (Pol I) and RNA polymerase III (Pol III) complexes. 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. Component of the RNA polymerase III (Pol III) complex consisting of 17 subunits. Directly interacts with the RPC40 subunit. Present with 8680 molecules/cell in log phase SD medium. Belongs to the archaeal Rpo11/eukaryotic RPB11/RPC19 RNA polymerase subunit family.