[Ammie]

why is it good to have a cytomegalovirus promoter in the cloning plasmid? I do not understand that, please explain to me?

[Jelanen]

So you can have an inducible promoter for expression in eukaryotic cells.

[Ammie]

Thanks!

But I already have T7, so what is the difference?

[Ammie]

Hi. Thinking about this T7 and CMV promoter again…

I have both in my plasmid.

I have understand that T7 polymeras can be used for in vitro/cell-free trancription. Is that what it is used for?

And CMV promoter as I understood it is good because than you dont need to make a RNA transcript of your gene (in a plasmid) instead you can transfect the whole plasmid when you want to express it in cells.

I still do not really get it. Could anyone explain the differences of those promoters for me or at least give me a hint.

[Duke]

quote Ammie:

Hi. Thinking about this T7 and CMV promoter again…

I have both in my plasmid.

I have understand that T7 polymeras can be used for in vitro/cell-free trancription. Is that what it is used for?

And CMV promoter as I understood it is good because than you dont need to make a RNA transcript of your gene (in a plasmid) instead you can transfect the whole plasmid when you want to express it in cells.

I still do not really get it. Could anyone explain the differences of those promoters for me or at least give me a hint.

T7: Inducible promoter for bacterial expression (e.g. pET system), needs T7 polymerase which is not present in native E.coli but needs to be expressed under the control of a DE3 gene (can be or usually is controlled by the lac-operon)

CMV: constitutive promoter for mammalian expression

Do you have a shuttle vector for both bacterial and mammalian expression?

The CMV promoter on a cloning plasmid is not of any use unless you would like to use the palsmid directly for expression of the protein in mammalian cells.

[Author]

Posts