RNA polymerase II is a large 12-subunit complex that synthesizes all mRNAs and several non-coding RNAs in eukaryotic cells. It is a DNA-dependent RNA polymerase enzyme that catalyzes transcription of DNA into RNA based on the four ribonucleoside triphosphate building blocks. RNA polymerase II is regulated through DNA-binding transcriptional regulators in both gene and cell type-specific manners.
