Index >> Protein Synthesis >> Transcription

Transcription - (1) Transcription requires a template (usually double-stranded DNA), ribonucleoside triphosphates (ATP, GTP, UTP, CTP), the enzyme RNA polymerase and divalent metal ions.

(2) RNA polymerase  consists of a core enzyme, with subunits (α, α, β, β, ω) and a sigma (δ) factor. The sigma factor initiates transcription of mRNA on the DNA template and the core enzyme continues transcription.

(3) All RNA chains start with either pppG or pppA and are synthesized in the 5'-->3' direction.

(4) Chain termination is brought about by a rho (P) factor.