利用TAKARA公司生产的cDNA Library Construction Kit构建了野桑蚕脑组织的cDNA文库,经鉴定文库的滴度达3.5×105pfu/mL,文库插入片段的平均大小为1.2kb。从文库的测序结果中获得野桑蚕化学感受蛋白基因(CSP3)完整的开放阅读框(登录号:EU439267)并对其进行了序列分析。结果表明:该基因读码框由384个核苷酸组成,编码127个氨基酸,分子质量为14.6kD。通过对该基因编码的氨基酸和其它17种昆虫的CSP编码的氨基酸进行进化分析,发现该基因与家蚕CSP3的同源性最高,达96.85%。该基因的发现对于研究家蚕和野桑蚕对化学农药的敏感性差异具有重要意义。
[Objective] The aim of the study is to construct cDNA library of midgut tissue of wild silkworm and isolate the serine protease gene. [Method] The midgut tissue-specific cDNA library of wild silkworm was constructed via cDNA Library Construction Kit (TaKaRa), then the serine protease gene was cloned via sequencing of the yielded cDNA library. [Result] The titer of cDNA library reached 6.2×105 pfu/ml, average insert size was about 1.2 kb. The serine protease gene cDNA fragment was obtained from colony sequencing (Accession No: EU672968). The nucleotide sequence of the cloned 854 bp fragment encodes 284 amino acid residues. Homology analyses showed some homology between putative amino acid sequence of the cloned fragment and amino acid sequences of serine proteases from other ten insects. [Conclusion] The results may avail to reveal the resistance of silkworm and wild silkworm to exotic intrusion.
[ Objective ] The aim of the study was to explore the resistance development of deltamethrin through selection of dettamethrin resistant strain of wild silkworm （ Bombyx Mandarina）, thus providing the basis for scientific pesticide application and resistance management. [ Method] The wild silkworms collected from three different regions were reared indoors, and the sensitivity of their parents to deltamethrin was detected by topical application. The larvae in each generation were treated with deltamethdn in median lethal dose or so by.topical application. The mortality of larva was analyzed for the establishment of toxicity regression equations and the calculation of the multiple or increased multiple of deltamethdn resistance.[Result] After the Qidong Bornbyx Mandarina （YQD） fed with mulberry leaves were selected for three generations indoors, the multiple of deltamethdn resistance of F, was 14.26, 1.2 times as great as that of Fo ; after the Bombyx Mandarina from mulberry garden of Soochow University （YSD） fed with mulberry leaves were selected for three generations indoors, the multiple of deltamethrin resistance of F4 was 16.48, 1.9 times as great as that of Fo ; after the Wujiang Bombyx Mandarina （YWJ） fed with artificial diets were selected for three generations indoors during six generations, the multiple of deltamethrin resistance of Fe was 18.67, 1.2 times as great as that of Fo. [ Conclusioa] With the selection in same dose, the resistance multiple of YSD increases more rapidly than that of YQD; under double selection of artificial diets and insecticide, the resistance multiple of YWJ increases more slowly than that of YQD.
