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why these guys use T7 instead of CMV? - for transfection (May/23/2011 )

I am reading a paper by Nakaya et al., 2001. In figure 1 they show cloning of the whole virus genome into a plasmid (must be pBR322) that has T7 promoter. and they transfect into HEp-2 cells. I have personally never used T7 promoter for transfection into Eukaryotic cells. We learned we must use CMV.

Click here to see the paper

-Curtis-

T7 is most commonly used to produce RNA via the a RNA polymerase for making probes for northerns and ISH, as opposed to the CMV promoter which is a viral promoter used for many eukarotic expression systems.

In theory you can use any promoter to produce RNA which will then be translated; it all depends on how much protein you want to be produced. If you want lots of protein use a plasmid with CMV or SV40 or other viral promoter as these are typically very high expression as a virus requires lots of protein in a short time. for lower expression you can use mammalian or insect promoters.

-bob1-

Amen,

Bob1, I can't recall how many times you've come to rescue me in the past 4 years, thank you so much.

-Curtis-