Help: low transfection efficiency but control works great

[Yulia Shifrin]

 Hello everybody!
I'm having problems with transfecting melanoma cells with vector containing
dsRed fused to my protein of interest. I'm using Fugene 6 and get 60-70%
efficiency with vector-only control, but only 1-5% efficiency with my
construct. The protein that I'm working on is pretty large (300 kDa). I'm
getting really frustrated. Has anybody encountered similar problems? What
can i do to improve the efficiency
Thanks in advance
 Yulia
<methods at net.bio.net>