Introduction of a foreign gene coding for a pathogen resistant protein into the target plant and constitutive expression of Resistance (R) proteins may confer high level of resistance. However, genetic engineering could lead to reprogramming of molecular mechanisms that manage physiological behavior, which in turn could lead to undesired results. Therefore, using a pathogen-inducible synthetic promoter approach, response to pathogens could be more specific. Ascochyta rabiei is a destructive fungal pathogen in chickpea production. In this study, we analyzed the expression pattern of three synthetic promoters in response to pathogen and two defense hormones. We have tested three synthetic pathogen-inducible promoters designated as (1) synthetic promoter-D box-D box (SP-DD), (2) synthetic promoter-F element-F element (SP-FF) and (3) synthetic promoter-F element-F element-D box-D box (SP-FFDD) via Agrobacterium transient expression assay. The cis-acting element designated as ‘D’ is a 31 base pair sequence from the promoter of parsley pathogenesis-related gene 2 (PR2 gene) and the cis-acting element designated as ‘F’ is a 39 base pairs sequence from the promoter of Arabidopsis AtCMPG1 gene. We used mycelial extracts from two pathotypes of A. rabiei as elicitor to define the responsiveness of the promoters against pathogen. Plant phytohormones including salicylic acid and methyl jasmonate were also used to study the promoter sensitivity in plant signaling pathways. Our results showed that the SP-FF promoter was highly inducible to A. rabiei and methyl jasmonate as well, while the SP-DD promoter was more sensitive to salicylic acid. The SP-FFDD promoter was equally responsive to both pathotypes of A. rabiei which is probably due to the complex nature of box D cis-acting element.

中文翻译：

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含有 F 和 D 顺式作用元件的合成启动子对 Rabiei 壳二孢和两种植物防御激素的瞬时表达分析。


将编码病原体抗性蛋白的外源基因引入目标植物并组成型表达抗性(R)蛋白可赋予高水平的抗性。然而，基因工程可能会导致管理生理行为的分子机制重新编程，进而可能导致不良结果。因此，使用病原体诱导的合成启动子方法，对病原体的反应可能更加特异。 Ascochyta rabiei是鹰嘴豆生产中的一种破坏性真菌病原体。在这项研究中，我们分析了三个合成启动子响应病原体和两种防御激素的表达模式。我们测试了三种合成病原体诱导型启动子，指定为（1）合成启动子-D盒-D盒（SP-DD），（2）合成启动子-F元件-F元件（SP-FF）和（3）合成启动子-F元件-F元件-D盒-D盒(SP-FFDD)通过农杆菌瞬时表达测定。指定为“D”的顺式作用元件是来自欧芹发病机制相关基因2（ PR2基因）的启动子的31个碱基对序列，并且指定为“F”的顺式作用元件是来自启动子的39个碱基对序列拟南芥AtCMPG1基因。我们使用来自两种狂犬病菌致病型的菌丝体提取物作为诱导子来确定启动子针对病原体的反应性。水杨酸和茉莉酸甲酯等植物激素也被用来研究植物信号通路中启动子的敏感性。我们的结果表明，SP-FF 启动子对狂犬病和茉莉酸甲酯也高度诱导，而 SP-DD 启动子对水杨酸更敏感。 SP-FFDD启动子对狂犬病两种致病型的反应相同，这可能是由于盒D顺式作用元件的复杂性质。