费尔干猪毛菜病程相关蛋白SfPR1a基因的异源表达增强了烟草对干旱、盐及叶斑病的抗性

Pathogenesis-related protein gene SfPR1a from Salsola ferganica enhances the resistances to drought, salt and leaf spot disease in transgenic tobacco

为明确一年生草本盐生植物费尔干猪毛菜(Salsola ferganica Drob.)病程相关蛋白基因SfPR1a (GenBank登录号为JQ670917)是否参与了植物对逆境胁迫的响应,采用qRT-PCR检测了该基因在不同组织部位和脱落酸(ABA)、茉莉酸(JAs)、乙烯合成直接前体(ACC)等相关激素胁迫及NaCl处理下的表达规律,同时对转基因烟草在盐、旱及丁香假单胞菌等胁迫下的抗性进行了鉴定。结果显示, SfPR1a基因在费尔干猪毛菜根中的表达量显著高于茎叶中,且受到ABA、JAs、ACC、NaCl的积极诱导;干旱胁迫下,转基因烟草的丙二醛(MDA)含量显著低于野生型烟草,显示出较强的抗旱表型;盐胁迫下,异源表达SfPR1a的转基因烟草幼苗生长显著优于野生型烟草;丁香假单胞菌攻毒后的转基因烟草叶片呈现严重的坏死反应,但植株的整体抗性表型显著优于野生型烟草;亚细胞定位结果显示该蛋白定位于植物细胞质外体空间。以上结果表明,费尔干猪毛菜病程相关蛋白SfPR1a基因参与了植物对非生物及生物胁迫的抗性。

In order to investigate whether SfPR1 a, a pathogenesis-related protein gene from an annual halophytic species Salsola ferganica Drob., was involved in the response to plant defense, qRT-PCR was employed to detect its expression patterns under abscisic acid(ABA), jasmonic acid(JAs), ethylene synthesis direct precursor(ACC), and Na Cl treatments. We also identified resistances to salt, drought and Pseudomonas syringae tomato(PstDC3000) of transgenic tobacco were identified. The expression of SfPR1 a gene in roots was significantly higher than that in shoots, and positively induced by ABA, JAs, ACC, and Na Cl treatments. The malondialdehyde(MDA) content of transgenic tobacco was significantly lower than that of wild-type tobacco,showing a strong resistance to drought. The ectopic expression of SfPR1 a gene improved plant growth under salt stress. After infection of P. syringae, transgenic tobacco leaves showed serious necrosis reaction, but the overall resistance phenotype of the plants was significantly better than that of WT. Subcellular localization analysis showed SfPR1 a was localized in the plant cell apoplastic space. The above results indicated that the SfPR1 a gene is involved in plant resistance to abiotic and biotic stresses.