Hi All,
I recently generated few constructs in pcDNA 3.1 HisC,encoding three different Fibronectin fragments.I did not realised that His tag was at the N terminal(I just overlooked). I transfected HEK293T cells,harvested cells after 72 hours, probed for His Tag and successfully detected His tagged FN at right position. As par I know the signal sequence undergoes some proteolytic processing through ER before it gets secreted into ECM. Can N terminal His Tag block its processing? I only managed to get a nice band for 2 of my constructs but third one is not working. I have also tried pSecTag2/Hygro B but it did not work at all. Can anyone suggest any Mammalian expression vector that has a C terminal Tag?