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What is What is the function of a promoter site on DNA? and explain in detail?
Promoter sites are initiation sites for transcription. Transcription stas when RNA polymerase binds to the promoter. It then unwinds the closed promoter complex, where DNA is in the form of a double helix, to form the open promoter complex in which about 17 base pairs of template DNA are unwound. RNA synthesis then begins with either a pppA or a pppG inseed at the beginning 5'-terminus of the new RNA chain, which is synthesized in the 5' to 3' direction. Ref: Weil P. (2011). Chapter 36. RNA Synthesis, Processing, & Modification. In D.A. Bender, K.M. Botham, P.A. Weil, P.J. Kennelly, R.K. Murray, V.W. Rodwell (Eds),Harper's Illustrated Biochemistry, 29e.