I am trying to transfect YTS, an NK cell line through nucleofection. When I use an empty vector, it easily gets expressed, while my gene of interest cloned in the same vector does not get expressed although I follow exactly the same protocol as for the empty vector. I thought that quality of DNA might be the problem. Hence, I PEG precipitated my DNA and repeated the same. But as usual there was no expression. In addition to that I see higher cell death when I use my gene of interest. And the pmax-GFP provided by Lonza gets highly expressed. Any reason, suggestion or insight will be highly appreciated.

Thank you.