Fig. 1.

Stabilization mechanisms for D. melanogaster. Relative positions of fluorescent markers (M1, M2, M3), the promoters (P1, P2), a gene of interest (GI), FRT sites (FRT3, FRT), the homing sequence linotte (HS), and the 5′/3′ transposable ends (triangles) are shown. a After partial remobilization via piggyBac transposase, stabilized flies contain only one 5′ piggyBac end (adapted from Handler et al. 2004). b After RMCE via FLP and heterospecific FRTs as well as subsequent partial remobilization via piggyBac transposase, stabilized flies contain only one 3′ piggyBac end (adapted from Horn and Handler 2005). c 5′/3′ piggyBac (black triangles) and Hermes (gray triangles) transposon ends are shown. FRT/FLP-induced inversion generates two immobile Hermes/piggyBac-hybrid insertions containing one Hermes and one piggyBac end. d All 5′ and 3′ transposable ends are piggyBac ends. After FRT/FLP-induced inversion, the two piggyBac insertions contain either only 5′ or only 3′ ends that makes each of them immobile. Please note: because of the genomic distance (dashed line) the two insertions cannot transpose together either