Marker allele that is present in transgenic constructs made using a 'FOFO1.0' based plasmid that contains an Act5C promoter; the construct is designed so that expression should only occur once both of the FRT and mFRT71 STOP cassettes located downstream of the Act5C promoter have been excised (requires both the FLP and FLPm5 recombinases, which target FRT and mFRT71 respectively). However, some read-through is occasionally seen in cases where both of the STOP cassettes have not been removed. The marker consists of EGFP tagged at the N-terminal end with the Tag:M(mCd8a) membrane targeting signal.