How to replace intron region in a plasmid? I'm considering working with the plasmid pRFHUE-eGFP and would like to replace the gpdA intron (which is the eGFP promoter region) with a promoter from another organism. What would be a good strategy for replacing the intron if I already have the other gene in-hand? Would I cut out the fragment between the SalI and SmaI restriction sites and then insert the new promoter with compatible overhangs there? ![enter image description here](

Your strategy would work, but if possible you might be better off using XmaI rather than SmaI, as the latter is a blunt-end cutting enzyme.

Furthermore, your strategy would not replace the entire _gpdA_ promoter, if that's what you're after. You might wanna refer to their paper, where it's clear from Fig. 1 that the promoter region is much longer than the region between SalI and SmaI:

![Fig 1. from Crespo-Sempere et al. \(2011\)](