rna polymerase is an
Compare RNA-dependent RNA polymerase. RNA polymerase (RNAP or RNApol), also known as DNA-dependent RNA polymerase, is an enzyme that produces primary transcript RNA. In cells, RNAP is necessary for constructing RNA chains using DNA genes as templates, a process called transcription.ach RNAP is transcribing an RNA strand, which can be seen branching off from the DNA. Begin indicates the 3' end of the DNA, where RNAP initiates transcription; End indicates the 5' end, where the longer RNA molecules are completely transcribed.