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. In line 100107015-HRA, the transposon inserted into intron 14. Western blot analysis confirmed the absence of protein expression in heart, liver, spleen, lung, small intestine and brain. (J:123680, J:219546)