Can shRNAmir/TRC constructs be packaged using a 293G cell line?
We are familiar with the 293G cell line but have not worked with it directly. It is a cell line that expresses the VSV-G envelope which is used to pseudotype the lentiviral particle. We don't believe that the 293G cell expresses any of the packaging components other than the VSV-G envelope. The VSV-G envelope expressed on the surface of the viral particle is what binds the virus to the surface of the target cell. When you co-transfect the 293G cells with the other lentiviral packaging components (Gag-Pol, Rev, and the gene transfer vector), it will then produce the lentiviral vector particles that have the VSV-G envelope. We use a similar cell line, 293T, to generate our virus stocks. The difference is that our cell line does not express the VSV-G envelope. Instead, we transfect an additional plasmid that encodes the VSV-G envelope cDNA along with the other packaging components.
The short answer is that both the shRNAmir and TRC constructs can be packaged in the 293G cell line.