is a short DNA sequence that signals the RNAPol
where to begin
transcription. Comparison of many E. coli DNA
shows two common promoter motifs [yellow boxes] with
similar sequences, which are
located approximately -10 [the TATA Box]
[the CAT Box] bases 5'
from the startpoint
of RNA transcription [blue box]. Similar promoter regions occur in
and eukaryotic genes.
It is important to
remember that the promoter
for the downstream startpoint of
at position +1. The startpoint of translation is recognizable in the
further downstream, but is actually on the transcribed RNA molecule, at the AUG
of the gene. [Note that the start codon does
not appear in the diagram].
Figure © 2004 by
Griffiths et al. ; text © 2011 by Steven M. Carr