Effect of N- or C-terminal location of GFP tag on localisation

In order to minimise the possibility of the GFP interfering with protein function and/or localisation, two separate populations of cDNAs were generated encoding N-terminal or C-terminal GFP fusions. Clearly this appears to be a crucial strategy, since overall only 56% of the proteins localised to a specific compartment irrespective of the position of the GFP. In the instances where only one fusion localised, the complementary fusion either gave no expression or a nuclear and cytosolic staining - characteristic for GFP alone expression.