DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB11 is part of the core element with the central large cleft (By similarity). Component of the RNA polymerase II (Pol II) complex consisting of 12 subunits. Belongs to the archaeal Rpo11/eukaryotic RPB11/RPC19 RNA polymerase subunit family.