The pgc promoter and 5'UTR (2777bp of genomic sequence from upstream of the pgc translation start site) are fused upstream of the EGFP coding sequence, followed by a mutated pgc 3'UTR, in which 8bp (UGUAAAUU) of a 10bp conserved sequence (UUUGUAAAUU) that closely matches the pum response element (PRE) has been deleted.