Schematic of composite vector and overview of genomic integration.

(A) The left half of the composite vector contains a 5′ ITR, a transposase gene under the control of the Dmhsp70 promoter and the 3xP3-ECFP transformation marker, while the right half contains both 5′ and 3′ ITRs, and is marked by both an EGFP gene under the control of the Dmhsp27 minimal promoter for enhancer trapping and a 3xP3-DsRed transformation marker. The transposase gene can be immobilized by the precise excision of the sequence between the central 5′ ITR and the 3′ ITR; in this case, larvae expressed ECFP alone. (B) Transformation markers expressed in the CNS of first instar larvae of H. axyridis indicate vector integration. From left to right, bright field, DsRed, ECFP and EGFP are presented in wild-type, composite vector (DsRed and ECFP are expressing), Jumpstarter (only ECFP is expressing) and Mutator (only DsRed is expressing). EGFP expression is not detected in all of strains. All panels display a ventral view (anterior uppermost).