Background

SA (Salicylic acid) and JA (Jasmonic acid)/ET (Ethylene) are the defense and growth hormone regulators involved in alleviating the biotic and abiotic stresses. WRKY and NAC genes are contributors to plant resistance due to their active role in SA and JA/ET defense mechanism.

Methods

WRKY and NAC transcription factors (ptHR293 and ptHR759, respectively) were serially selected (by performing cDNA library functional screening, homology analysis, antioxidant enzymes, ROS burst, callose deposition and qRT-PCR analysis) from Pinellia ternata and transformed into Nicotiana benthamiana. Hybrids were generated to analyze the stability of disease resistance. UPLC-QTOF-MS was performed to study the bioactive compounds.

Results

Study demonstrated that ptHR293 and ptHR759 had potential to trigger ROS burst and callose deposition in N. benthamiana together with the activation of PR-genes and antioxidant enzymes. In transformed N. benthamiana, relative expression of PR-1a (Pathogenesis related-1a) and PDF1.2 (Plant defensin 1.2) was upregulated upto 21 folds and 4 folds for ptHR293 transformed N. benthamiana. While PR-1a and PDF1.2 exhibited 8 folds and 26 folds upregulation for ptHR759 transformed N. benthamiana. ptHR293 + ptHR759-F₁ hybrids also exhibited a significant level of PR-gene expression. Significantly high resistance against Botrytis cinerea without influencing the standard seed germination, root and shoot length of transformed N. benthamiana was also observed. A significant induction of bioactive compounds was also observed in ptHR293 transformed N. benthamiana.

Conclusion

Conclusively, heterologous transcription factors, ptHR293 and ptHR759, perform their specific role in the activation of SA and JA/ET mediated defense mechanism.

中文翻译：

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异源WRKY和NAC转录因子触发了本氏烟草的抗性

背景

SA（水杨酸）和JA（茉莉酸）/ ET（乙烯）是参与缓解生物和非生物胁迫的防御和生长激素调节剂。WRKY和NAC基因在SA和JA / ET防御机制中发挥积极的作用，是植物抗性的贡献者。

方法

从半夏中连续选择WRKY和NAC转录因子（分别为ptHR293和ptHR759）（通过进行cDNA文库功能筛选，同源性分析，抗氧化酶，ROS猝灭，call质沉积和qRT-PCR分析），并将其转化为本氏烟草。产生杂种以分析抗病性的稳定性。进行了UPLC-QTOF-MS研究生物活性化合物。

结果

研究表明，ptHR293和ptHR759具有触发本氏烟草中ROS破裂和burst质沉积以及PR基因和抗氧化酶活化的潜力。在转化的本氏烟草中，PR- 1293（病原相关1a）和PDF1.2（植物防御素1.2）的相对表达上调了ptHR293转化的本氏烟草21倍和4倍。而PR-1a和PDF1.2对ptHR759转化的本氏烟草进行了8倍和26倍的上调。ptHR293  +  ptHR759 -F ₁杂种也表现出显着水平的PR基因表达。在不影响标准种子萌发的情况下，对灰葡萄孢具有显着的高抗性，还观察到转化的本氏烟草的根和茎长。在ptHR293转化的本氏烟草中也观察到明显的生物活性化合物的诱导。

结论

结论是，异源转录因子ptHR293和ptHR759在SA和JA / ET介导的防御机制的激活中发挥其特定作用。