jr at dna.bio.warwick.ac.uk wrote:
: Dear all,
: Maybe someone out there can help me with this question regarding the
: T7 RNA promoter. So far as I can find out the promoter sequence is:
: (From the Stratagene catalog)
: TAATACGACTCACTATA *GGG
: in which transcription initiates at the first G residue of the three G's and
: is marked with an asterix
: My question is : Do those three G's have to be there or could I replace the
: three G's without loss of transcription activity?
: I would ideally like to replace them with TGC. This is so as to intiate
: transcription at a start of my insert. (Before someone posts asking why I'm
: doing this since translation would occur further down and therefore I
: don't need to change the T7 promoter sequence, let me say its just a long
: story and the work necessitates this change. If you really want to know I
: don't mind E-mailing responses.)
Tom Schneider did a randomization study on T7 RNAP sites which
is quite interesting; you will probably find a suitable answer there.
Excess information at bacteriophage T7 genomic promoters detected by
a random cloning technique. Nuc.Acids.Res 17:659-674
See also:
Schneider et al. JMB 188:415-431
Enjoy & good luck!
Keith Robison
Harvard University
Department of Cellular and Developmental Biology
Department of Genetics / HHMI
robison at mito.harvard.edu
