Expression of protein - CMV promoter

[Basia Dymek]

Hi!
I have prepared a plasmid using pFLAG-CMV-2 vector (Sigma) into which I have
cloned my gene of interest. Finally, I have some level of expression after
transfection HepG2 cells, however it is unsatisfactory for me. CMV promoter
should be the strong one. Have you got any clues what could be the reason of
low level of expression of my protein? I would be thankful for any advice.
Basia