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隐地蛋白(cryptogein, Crypt)是由隐地疫霉(Phytophthora cryptogea)分泌的一种分子量约为10 kD的蛋白类激发子. 用农杆菌介导的叶盘转化法获转Crypt (PAL::Crypt)和CryK13V (CaMV35S::CryK13V) 基因的烟草植株. 接种试验结果表明, T2代转基因烟草株系对黑胫病菌(Phytophthora parasitica var nicotiana, Ppn)、赤星病菌(Alternaria alternata)和野火病菌(Pseudomonas syringae pv tabaci)的抗性显著增强. Northern杂交和RT-PCR分析结果表明, 低水平的表达转化基因Crypt和CryK13V就足以激活PR-1a和PR-5等防卫反应相关基因的表达; 在PAL::Crypt转化系统中, 病原菌Ppn能快速和高水平诱导PR-1a等病程相关基因的表达, 表明诱导型PAL启动子对入侵病原菌能及时识别并快速、有效地激活防卫反应, 从而赋予转基因植株抵抗病原菌侵染的能力. 研究还发现, 表达Crypt和CryK13V基因的烟草植株耐盐性比对照明显提高, 转化株系中高水平组成型表达PR基因和转录因子可能与耐盐性增强有一定正相关性. 上述结果表明, 植物对生物和非生物逆境的抗性途径和机制存在着交叉.
Cryptogein (Crypt) is a protein-based exciton secreted by Phytophthora cryptogea with a molecular weight of about 10 kD. Crypt was transformed by Agrobacterium-mediated leaf disc transformation (PAL :: Crypt) and CryK13V (CaMV35S :: CryK13V) were obtained.The results of inoculation showed that the transgenic tobacco plants of T2 generation had higher sensitivity to Phytophthora parasitica var nicotiana (Ppn), Alternaria alternata and Pseudomonas syringae pv tabaci.The results of Northern hybridization and RT-PCR showed that Crypt and CryK13V were low enough to activate defense-related genes such as PR-1a and PR-5, : Crypt transformation system, the pathogen Ppn can quickly and high level of PR-1a and other pathogenesis-related gene expression, indicating that the inducible PAL promoter invasion of pathogens can promptly identify and promptly and effectively activate the defense response, thereby giving resistance to transgenic plants Pathogen infection.The study also found that Crypt and CryK13V gene expression in tobacco plants significantly increased salt tolerance than the control, the high level of the transformed line group PR gene expression and transcription factors may have a positive correlation with enhanced salt tolerance. The above results show pathways and mechanisms of resistance of plants to biotic and abiotic stresses present in the cross.