The DNA dependent RNA polymerase helps in DNA replication by catalysing the polymerisation in only one direction, i.e., 5′→3′. In bacteria, the RNA polymerase has co-factors b, b′, a, a′, w and s which catalyse the process.
Initiation: s (sigma) factor recognises the start signal and promotor region on DNA and the s (sigma) with RNA polymerase binds to the promoter and initiate transcription.
Elongation: The RNA polymerase after initiation of RNA transcription loses the s-factor but continues the process of RNA formation.
Termination: Once the RNA polymerase reaches the termination region of DNA, the RNA polymerase is separated from DNA–RNA hybrid, as a result nascent RNA separates. This process is called termination which is facilitated by certain termination factor ρ.
