人工合成gna基因在小麦中的表达及其抗蚜虫效果研究

利用经密码子优化的、人工合成雪花莲凝集素(Galanthusnivalisagglutinin),gna基因及RbcS启动子构建了高效特异表达载体pBAC202,通过基因枪轰击小麦幼胚和幼穗,将外源gna基因导入到3个高产小麦(TriticumaestivumL.)品种中,获得42个转基因后代株系。对转基因后代植株进行了DNA点杂交、PCR及PCR-Southern验证,确认外源gna基因已成功地整合到小麦基因组中。进一步的凝集素活性检测表明,小麦叶片中表达的凝集素可使红细胞凝集,并具有正常的生物学活性。转基因植株在人工饲养条件下进行抗蚜虫(Rhopalosiphumpadi)试验,蚜口密度抑制率从19%～73%不等,部分株系抑虫效果较好。利用转基因的方式可将外源抗虫基因gna导入到小麦中,并可有效地增强小麦的抗蚜能力,为选育具抗虫特性的优质小麦提供新的途径。

Expression of Synthesized Snowdrop Lectin(gna) Gene in Transgenic Wheat and Its Resistance Analysis against Aphid

An expression vector pBAC202 containing a synthesized gene encoding snowdrop lectin (Galanthus nivalis agglutinin, GNA) driven by RbcS tissue-specific expression promoter was constructed and then transferred into indigenous high yield wheat (Triticum aestivum L.) cultivar explants of immature inflorescence and immature embryos by particle bombardment method. Forty-two transformed plants were derived. DNA Dot blotting, PCR and PCR-Southern hybridization analysis were performed and the exogenous gene integration was confirmed. Protein extracted from leaf of positive transgenic plants were subjected to red blood cell agglutination bioassay; the experimental result showed that the selected transformants had expressed GNA with normal biological function. The aphid (Rhopalosiphum padi) resistance bioassay were carried out under artificial condition; the aphid reduction rate in different transgene lines ranged from 19%to 73% based on statistic data and some transgenic lines demonstrated strong against aphid resistance capability. Transgenic approaches using insecticidal genes such as gna present promising opportunities for wheat molecular breeding and the control of damaging wheat pests.