What is a gene
of a DNA transcriptional unit to its transcribed RNA product:
RNA is transcribed from the template strand
DNA. As with all
acids syntheses, the RNA product
is transcribed 5'
signal for the
start of transcription is the promoter, which is 'upstream'
is, 5' to) with
respect to the
the DNA. The first
transcribed base is several bases downstream (that
is, 3' to) from the
Transcription then proceeds to a signal sequence at the termination
The transcribed product thus includes a 5' untranslated region (5'-UTR) upstream from the
begining of translation at the start codon, and a 3'-UTR downstream from the
translation at the stop codon. These, like the intron regions,
removed before the protein product is translated from the RNA.
Figure modified after © 2002
Griffiths et al. ; text © 2011 by Steven M. Carr