title: A transgenic embryonic sexing system for Anastrepha suspensa (Diptera: Tephritidae).
abstract: The Sterile Insect Technique (SIT) is a highly successful biologically-based strategy to control pest insect populations that relies on the large-scale release of sterilized males to render females in the field non-reproductive. For medfly, a mutant-based sexing system is available as well as a transgenic system where a tetracycline-suppressible (Tet-off) toxic molecule is female-specifically produced. However, the former classical genetic system took many years to refine, and the latter system results in female death by a poorly understood mechanism, primarily in the pupal stage after rearing costs have been incurred. Here we describe a Tet-off transgenic embryonic sexing system (TESS) for Anastrepha suspensa that uses a driver construct having the promoter from the embryo-specific A. suspensa serendipity α gene, linked to the Tet-transactivator. This was used to drive the expression of a phospho-mutated variant of the pro-apoptotic cell death gene, Alhid, from Anastrepha ludens. The system uses a sex-specific intron splicing cassette linked to a cell death gene lethal effector. Progeny from TESS strains heterozygous for the transgene combination were 80-100% males, whereas four double homozygous TESS strains had 100% male-only progeny, with female death limited primarily to embryogenesis. In a large-scale test, more than 30,000 eggs from two strains resulted in 100% male-only progeny. The transgenic sexing approach described here is highly effective and cost-efficient by eliminating most, if not all, female insects early in embryogenesis using a well-characterized apoptotic mechanism.
authors.affiliation: USDA/ARS, Center for Medical, Agricultural and Veterinary Entomology, 1700 SW 23rd Drive, Gainesville, FL 32608, USA. mfas@ufl.edu
authors.forename: Marc F
authors.initials: MF
authors.lastname: Schetelig
authors.forename: Alfred M
authors.initials: AM
authors.lastname: Handler
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics / Q000502:physiology*; D005260:Female; D007246:Infertility / Q000235:genetics / Q000503:physiopathology; D008297:Male; D010572:Pest Control, Biological / Q000379:methods*; D012726:Sexual Behavior, Animal; D033621:Tephritidae / Q000235:genetics / Q000502:physiology*; D019076:Transgenes