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Control protein for eukaryotic expression - (Oct/04/2013 )

Hi Guys,


I am new to the forum, and so do I in recombinant protein expression in eukaryotic cells :-)

I am trying to set-up a recombinant protein expression in my lab, with HEK293 cells and CHO cells (expression vector: pcDNA3). For the moment I will try transient expression.

I was wondering if someone could advice to me a good positive control (I mean a protein) to validate my culture and transfection procedure. I mean, can someone tell which protein will be expressed for sure with pcDNA3/HEK293 or pcDNA3/CHO ?

Thanks a lot for your help.


PS: sorry for my poor english.



If you wish to check the transfection efficiency you can use GFP driven by the same promoter as pCDNA3.




Thanks for your reply. The aim is not (only) to check tranfection efficiency, but also to check protein production/purification yield (after one-step IMAC).

Is the GFP expressed at good level ?



 i think you want to choose a protein to opyimize the purification system. so why not to choose an easily-done protein, such as GST. 

 best wishes.


Hi IBMSterry,


Thanks for your reply. Using a protein easy to purify is a good idea. Do you think that GST from pGEX vectors (S.japonicum) would be a good choice ?

Having that said, has anyone ever expressed a human recombinant in HEK293 with good expression rate ? To be honest, I would prefer this kind of control for my expression system.


HEK's are marvelous for expression studies. Whenever I have a problematic expression vector, I stick it into HEK's and see marvelous expression. HEK cells are a good choice.