唐菖蒲GhAOS基因的表达特性及其在拟南芥中的过表达分析

【目的】分析唐菖蒲AOS基因的表达模式及其对JAs生物合成的影响，研究GhAOS基因对伤害胁迫的应答机理。【方法】利用基因枪的方法进行GhAOS的亚细胞定位分析；运用Real-time RT-PCR技术分析GhAOS基因的表达模式，采用农杆菌介导的侵染拟南芥花粉法进行GhAOS基因的过表达分析。【结果】GhAOS定位在叶绿体的内囊体膜上；该基因在唐菖蒲各组织中均表达，其中在籽球和匍匐茎中表达量最高；经过0.1-0.5 mmol•L-1的茉莉酸甲酯（MJ）处理后，逐渐提高了GhAOS在球茎中的表达量和内源MJ含量；在拟南芥中过量表达该基因，提高了拟南芥的耐盐性和抗旱性；经过机械损伤后提高了转基因拟南芥相关基因的表达水平和内源MJ含量。【结论】GhAOS促进了唐菖蒲茉莉酸类化合物（JAs）的生物合成，提高了拟南芥的耐盐性和抗旱性；转基因拟南芥机械损伤后提高了相关抗性基因的表达水平以及内源MJ的含量。

Analysis of GhAOS Expression Characteristics in Gladiolus hybridus and Overexpression in Arabidopsis

【Objective】The objective of this study is to analyze the expression pattern of GhAOS and the effect of this gene on JAs biosynthesis in Gladiolus hybridus,and study the response mechanism of the GhAOS gene to damage stress in plant.【Method】The technology of gene gun bombardment was used to analyze the sub-cellular localization of GhAOS.The real time RT-PCR was used to analyze the expression pattern of GhAOS.Agrobacterium-mediated genetic transformation system of Arabidopsis was also used to analyze the overexpression of GhAOS.【Result】The result of sub-cellular localization showed that the GhAOS-GFP fussion protein was targeted into the chloroplast thylakoid membrance.Real time RT-PCR analysis showed that the relatively high expression level of GhAOS was observed in stolons and cormels,and the expression level in corms steadily increased under MJ treatment with a raising concentration gradients from 0.1 mmol·L-1 to 0.5 mmol·L-1.Meanwhile,the endogenous MJ content was also correlated with the expression level of GhAOS.In addition,the salt tolerance and drought-resistance were increased in the overexpression Arabidopsis plants,and the related resistance genes and the endogenous MJ content were increased after mechanical damage.【Conclusion】GhAOS gene promoted JAs biosynthesis in Gladiolus hybridus,and increased the salt tolerance and drought-resistance in Arabidopsis.AOS gene expression may play a major readjustment function on the signal of JA in Gladiolus hybridus,and it may be closely related with the activation of some defense genes.After mechanical damage,the expression level of related resistance genes and the content of endogenous MJ were increased.