SV40, large T antigen and transformed cells???

[Nigel Kenward]

Hi Alistair,
I'm using pcDNA3 successfully to express a weird protein.
The bottom line is this:
In COS1 or 7 (or and other cell with the Large T you get MASSIVE 
overexpression of your protein (if everything else is OK !). This is due 
to the Large T interacting with the relevant site present on pcDNA3.
In cell types that don't have large T you will get overexpression 
(mainly due to the RSV promoter etc) and you will be able to make stable 
transfectants using antibiotic resistance.

Mind you, before you start it might be worth you looking at Promega's 
new plasmid, "pCI-neo". According to promega it produces 40 - 300 x more 
protein than pcDNA3 in stable transfectants, and even better results 
with transient transfections in COS7 cells (see Promega notes no. 51).

Hope this helps. (I don't work for Promega by-the-way)
TTFN,
Nigel Kenward.

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