RNA Polymerase ► | DNA-directed
RNA polymerase catalyzes
the synthesis of RNA on a DNA template. The core
enzyme has three polypeptide subunits: alpha, beta, & beta' in
a stoichiometry of α2ββ'
& an
additional subunit, omega. Core RNA
polymerase can bind to DNA and catalyze the
synthesis of RNA, but has no
specificity, it needs a 5th subunit, sigma
factor to
make it the
holoenzyme, with specificity. SUBUNITS: beta- β - involved in catalysis; chain initiation and elongation. beta prime - β' - binds to the DNA template. sigma - σ - directs enzyme to promoter, begins specific transcription.
omega - ω - required to restore denatured RNA
polymerase |
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