RNA Polymerases

RNA Polymerase, also known as RNAP, RNApol, or DNA-dependent RNA polymerase, synthesizes ribonucleotides into an RNA oligonucleotide chain. Unlike DNA polymerases, they can initiate synthesis without a primer and also lack exonuclease activity. The bacterial RNA polymerase core enzyme, a 400-kDa five-subunit complex, synthesizes both coding and non-coding RNA. Eukaryotic RNA polymerases are more complex, contain more subunits, and are more specialized. Five different types have been classified, each synthesizing different types of RNA: rRNA (Pol I); mRNA, snRNA and miRNA (Pol II); tRNA and 5S rRNA (Pol III); plant siRNA (Pol IV and Pol V). Viral polymerases are diverse and many types do not closely resemble the bacterial or eukaryotic polymerases. However, a few have become distinguished for use in in vitro RNA synthesis, such as the SP6, T7, and T3 RNA polymerases. Visit the supplier page for more detailed enzyme information.