title: Improved injection needles facilitate germline transformation of the buckeye butterfly Junonia coenia.
abstract: Germline transformation with transposon vectors is an important tool for insect genetics, but progress in developing transformation protocols for butterflies has been limited by high post-injection ova mortality. Here we present an improved glass injection needle design for injecting butterfly ova that increases survival in three Nymphalid butterfly species. Using the needles to genetically transform the common buckeye butterfly Junonia coenia, the hatch rate for injected Junonia ova was 21.7%, the transformation rate was 3%, and the overall experimental efficiency was 0.327%, a substantial improvement over previous results in other butterfly species. Improved needle design and a higher efficiency of transformation should permit the deployment of transposon-based genetic tools in a broad range of less fecund lepidopteran species.
authors.affiliation: Department of Biological Sciences, University of Manitoba, Winnipeg, Canada.
authors.forename: Kahlia
authors.initials: K
authors.lastname: Beaudette
authors.affiliation: Department of Biology, Western Kentucky University, Bowling Green, KY; Center for Human Genetics Research, Vanderbilt University, Nashville, TN.
authors.forename: Tia M
authors.initials: TM
authors.lastname: Hughes
authors.affiliation: Department of Biological Sciences, University of Manitoba, Winnipeg, Canada; Department of Biology, Western Kentucky University, Bowling Green, KY.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Marcus
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001426:Bacterial Proteins; D002080:Butterflies / Q000235:genetics*; D004251:DNA Transposable Elements; D004867:Equipment Design; D005260:Female; D018014:Gene Transfer Techniques / Q000295:instrumentation*; D005822:Genetic Vectors; D008164:Luminescent Proteins; D008297:Male; D009339:Needles; D010063:Ovum; D014170:Transformation, Genetic
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D008164:Luminescent Proteins; C054562:yellow fluorescent protein, Bacteria
keywords: common buckeye butterfly (Junonia coenia); germline transformation; injection needle design; question mark butterfly (Polygonia interrogationis); red admiral butterfly (Vanessa atalanta)