I am about to order a vector for bi-cystronic expression of peptide of interest and GFP as a marker. I will only use GFP as a marker to select infected cells. Does anyone gave experience with IRES sequence between peptide of inteterest and GFP? That seems like a good strategy as opposed to P2A to avoid any extra bits attached to the peptide of interest. Any advice from first hand experience will be helpful. We would like to express peptide of interest in sensory neurons - the peptide has ER targeting signal at the N-terminus that is why I am reluctant to put it after GFP marker with P2A in between

Thanks