The transposon containing an unspecified hybrid actin promoter driving expression of red fluorescent protein (RFP) flanked by piggyBac-specific left and right terminal sequences was co-injected with a piggyBac-containing transgene to mobilize the transposon. The transposon DNA fragment containing RFP sequence was inserted between exon 4 and 5 of gene. (J:123680, J:335806)