Submitted to: Nature Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/1999
Publication Date: N/A
Citation: Interpretive Summary: The protection of crops and stored commodities from insect pests is important. The expected loss of many insecticides because of acquired resistance or environmental hazard has left the industry with fewer options for pest control. Scientists at the USDA ARS, Center for Medical, Agricultural and Veterinary Entomology in collaboration with scientists in Japan and France developed a gene vector system for introduction of genes into insects. The piggyBac gene vector system was used to produce transgenic silkworms which demonstrates the utility of the vector system in Lepidoptera and establishes functionality of foreign genes carried within the vector. This system can be developed for genetic modification of pest insects for use in sterile insect release as part of integrated pest management programs.
Technical Abstract: A modified piggyBac transposon that included a chimeric fusion of the cytoplasmic actin gene BmA3 promoter and a Green Fluorescent Protein (GFP) encoding sequence was tested as a gene vector (pPIGA3GFP) in two strains of Bombyx mori. Preblastoderm eggs were microinjected with the vector along with a non-autonomous piggyBac helper that produced the requisite transposase activity for vector mobility. Two percent of the G1 broods had individuals that expressed GFP. Multiple independent insertions of the piggyBac vector were identified in the GFP-positive G1 progeny, and the pPIGA3GFP inserts were stably inherited by the G2 progeny. The presence of the inverted terminal repeats of piggyBac and of the characteristic TTAA insertion site sequence at the borders of all the inserts analysed confirmed that the transformation events resulted from precise piggyBac transposition. This is the first successful germ-line transformation reported for Lepidoptera and provides a foundation for promising basic and biotechnological applications.