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EM7 promoter - what is it? - (Jan/04/2015 )

I've been having a bit of difficulty finding out information about the EM7 promoter. So far the only info I've found is that the EM7 promoter is a synthetic modification of the bacteriophage T7 promoter. Does anyone else know anything more about this promoter and why it is used?

 

The plasmid I'm working with has an EM7 promoter which drives expression of the blasticidin resistance gene to allow for selection in mammalian cells. However, we are having issues generating stable cell lines and are wondering if promoter competition is occurring with the CMV promoter.

 

Cheers

-brookew-

They don't compete with each other. EM7 promoter is just a small piece of random DNA when in your mammalian cell line. If your stable cells need blasticidin selection, they will depend upon the eukaryotic promoter (such as CMV, SV40), which is generally put in tandem with prokaryotic promoter (such as EM7, T7) for antibiotic expression in bacteria. In other words..

 

EM7 promoter is derived from T7 promoter; both are prokaryotic promoters that allow expression of antibiotic genes in e.coli (such as blasticidin)

CMV promoter is eukaryotic promoter that allows expression of antibiotics (or any other) genes in mammalian cell lines.

-CPRES-