title: Establishment of an RTA-Bddsx hybrid system for female-specific splicing that can affect the sex ratio of Bactrocera dorsalis (Hendel) after embryonic injection.
abstract: BACKGROUND
  The oriental fruit fly, Bactrocera dorsalis (Hendel), a very destructive insect pest in many areas of Asia, including Taiwan, can cause significant damage by ovipositing in and larval feeding on many kinds of fruit. A female lethal system, combining the splicing property of doublesex (dsx) with the toxicity of ricin A chain (RTA), has been developed. In this system, a modified RTA is separated by Bddsx intron 3; the expressed RNA can only be spliced in females, with toxic effects, whereas the immature RTA in males is harmless.
  
  
  RESULTS
  Two RTA-Bddsx constructs, clone BE 24-7 and clone CF 26-21, containing Bddsx intron 3 and its flanking exonic sequences, with four nucleotides at the 5'-end and five nucleotides at the 3'-end, correctly spliced in a sex-specific manner. Wild-type and modified RTAs expressed in an Escherichia coli system retained their ability to suppress protein synthesis: 90.4% for Ricin-WT, 71.3% for Ricin-LERQ and 58.0% for Ricin-FEGQ. Embryonic injection of Acp-CF26-21, the RTA-Bddsx gene driven by the actin 5C promoter, resulted in a significant increase in male percentage in the eclosed adults.
  
  
  CONCLUSIONS
  Our results indicate that the RTA-Bddsx hybrid system offers a novel and promising approach for oriental fruit fly control.
authors: Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan.
authors: Chun-Yen
authors: CY
authors: Huang
authors: Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan.
authors: Chia Chia
authors: CC
authors: Huang
authors: Department of Entomology, National Chung-Hsing University, Taichung, Taiwan.
authors: Shu-Mei
authors: SM
authors: Dai
authors: Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan.
authors: Cheng
authors: C
authors: Chang
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D005260:Female; D005638:Fruit / Q000469:parasitology; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D007814:Larva; D008297:Male; D010058:Oviposition; D010935:Plant Diseases / Q000469:parasitology*; D010944:Plants / Q000469:parasitology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011993:Recombinant Fusion Proteins; D012276:Ricin / Q000235:genetics* / Q000378:metabolism; D012744:Sex Ratio; D033621:Tephritidae / Q000235:genetics* / Q000502:physiology
chemical_list: D019476:Insect Proteins; D011993:Recombinant Fusion Proteins; D012276:Ricin
keywords: Bactrocera dorsalis (Hendel); doublesex gene (dsx); female-specific splicing; ricin A chain (RTA)