Handler A M, Zimowska G J, Armstrong K F
Center for Medical, Agricultural, and Veterinary Entomology, Agricultural Research Service, U.S. Department of Agriculture, Gainesville, FL 32608, USA.
Insect Mol Biol. 2008 Aug;17(4):387-93. doi: 10.1111/j.1365-2583.2008.00813.x.
The piggyBac IFP2 transposable element, originally discovered in a Trichoplusia ni cell line, also exists as nearly identical elements in other noctuid lepidopterans, and in several species of the tephritid genus Bactrocera. To further define the distribution of piggyBacs in Bactrocera, and compare their relationship to sequences found in Lepidoptera, a survey by PCR amplification was performed in a range of Bactrocera species. Highly similar piggyBac sequences were found in all B. dorsalis complex species tested, as well as in species in the B. zonata and B. frauenfeldi complexes. All nucleotide sequences had > 94% identity to corresponding sequences in the T. ni IFP2 element, and > 88% identity among the sequences. Conserved primers did not amplify any distantly related sequences that have been found by computational searches in a wider range of insect and non-insect species. Notably, 55 nucleotide substitutions relative to IFP2 were common to all the Bactrocera sequences, 44 of which exist in piggyBacs previously sequenced from moths, with 17 resulting in amino acid substitutions. These piggyBac elements, that apparently traversed orders by horizontal transfer, probably arose from a lineage separate from IFP2 and the other known elements in T. ni. Implications for the presence of nearly identical piggyBacs, in widely distributed insects, to the applied use of piggyBac vectors are discussed.
最初在粉纹夜蛾细胞系中发现的piggyBac IFP2转座元件，在其他夜蛾科鳞翅目昆虫以及实蝇属的几种果实蝇中也以几乎相同的元件形式存在。为了进一步确定piggyBacs在果实蝇中的分布，并比较它们与鳞翅目昆虫中发现的序列的关系，我们对一系列果实蝇物种进行了PCR扩增调查。在所有测试的橘小实蝇复合种以及条带实蝇复合种和弗氏实蝇复合种的物种中都发现了高度相似的piggyBac序列。所有核苷酸序列与粉纹夜蛾IFP2元件中的相应序列具有> 94%的同一性，并且这些序列之间具有> 88%的同一性。保守引物没有扩增出通过计算搜索在更广泛的昆虫和非昆虫物种中发现的任何远缘相关序列。值得注意的是，相对于IFP2，55个核苷酸替换在所有果实蝇序列中是常见的，其中44个存在于先前从蛾类测序的piggyBacs中，17个导致氨基酸替换。这些piggyBac元件显然通过水平转移跨越了目，可能起源于与IFP2和粉纹夜蛾中其他已知元件不同的谱系。本文讨论了在广泛分布的昆虫中存在几乎相同的piggyBacs对piggyBac载体应用的影响。
