I stably transfected my cell line with a plasmid carrying a mutation of my gene of interest (GOI) which is tagged to HA.
After lentiviral stable transfection, I collected the protein from stable cell lines and found very high HA expression. However, when I sent my DNA from these stable cell lines for sequencing, I do not see a mutation in my GOI. But there is high expression of HA-tagged protein in my western.
I selected the cells with puromycin following transfection.
I'm a bit confused and would appreciate any suggestions.