The T2A viral peptide followed by the GAL4 open reading frame has been inserted in frame into the endogenous gce locus, just upstream of the stop codon. The presence of the T2A peptide is designed to ensure that the GAL4 driver sequence is translated independently and not as a fusion protein with the upstream coding sequence of the endogenous gce locus.
In adults, ScerGAL4gce-T2A-GAL4 is expressed across the brain. Strong expression seen in the mushroom body and weak expression in nodulus subunit II compared to the other subunits. Expression is absent from T5 cells/lobula layer 1 and the lobula plate as well as Medulla layer M10.