Hebei Branch of Chinese National Maize Improvement Center, Hebei Agricultural University, Baoding, People's Republic of China.
BMC Genet. 2019 Jul 26;20(1):63. doi: 10.1186/s12863-019-0766-4.
The tryptophan-arginine-lysine-tyrosine (WRKY) transcription factors play important roles in plants, allowing them to adapt to environmental conditions that are not normally conducive to plant growth; in particular, drought. There has been extensive research on WRKY transcription factors and the effects of their overexpression in plants on resistance to drought stress. However, due to the materials (the type and species of donor and receptor, promoters) and treatments (the type and time of stress) used, different and often confounding results have been obtained between studies. Meta-analysis is a powerful statistical tool that can be used to summarize results from numerous independent experiments on the same research topic while accounting for variability across experiments.
We carried out a meta-analysis of 16 measured parameters that affect drought resistance in plants overexpressing WRKY transcription factors and wild-type plants. We found that only one of these parameters was significantly different between transgenic and wild-type plants under drought and control conditions at a 95% confidence interval (p = 0.000, p = 0.009, respectively). Eleven of the sixteen parameters were obviously different in WRKY transgenic plants under drought and control conditions (SV, p = 0.023, SSC, p = 0.000, SOD, p = 0.012, SFW, p = 0.000, RL, p = 0.016, Pro, p = 0.000, POD, p = 0.027, MDA, p = 0.000, HO, p = 0.003, EL, p = 0.000, CHC, p = 0.000, respectively), seven of the eleven obviously different parameters showed positive effect (SSC, SOD, Pro, POD, MDA, HO, EL), four of them revealed negative effect (SV, SFW, RL, CHC).
We have found that only one of these parameters was significantly different between transgenic and wild-type plants under drought and control conditions respectively, at a 95% confidence interval. And eleven of sixteen parameters showed obviously different of WRKY-overexpressed plants under different conditions (water-stressed and normal), suggesting that WRKY transcription factors play an important role in plant responses to drought stress. These findings also provide a theoretical basis for further study of the role of WRKY transcription factors in the regulation of plant responses to environmental stress.
色氨酸-精氨酸-赖氨酸-酪氨酸（WRKY）转录因子在植物中发挥着重要作用，使它们能够适应不利于植物生长的环境条件；特别是干旱。人们对 WRKY 转录因子及其在植物中的过表达对干旱胁迫抗性的影响进行了广泛的研究。然而，由于使用的材料（供体和受体的类型和物种、启动子）和处理方法（胁迫的类型和时间）不同，不同研究之间的结果往往存在差异和混淆。元分析是一种强大的统计工具，可以用来总结同一研究课题的大量独立实验的结果，同时考虑到实验之间的变异性。
我们对 16 个影响过表达 WRKY 转录因子的植物抗旱性的测量参数进行了元分析，并与野生型植物进行了比较。我们发现，在干旱和对照条件下，只有一个参数在转基因和野生型植物之间的差异在 95%置信区间内具有统计学意义（p=0.000，p=0.009）。在干旱和对照条件下，WRKY 转基因植物的 16 个参数中有 11 个明显不同（SV，p=0.023，SSC，p=0.000，SOD，p=0.012，SFW，p=0.000，RL，p=0.016，Pro，p=0.000，POD，p=0.027，MDA，p=0.000，HO，p=0.003，EL，p=0.000，CHC，p=0.000），其中 7 个明显不同的参数表现出正向效应（SSC、SOD、Pro、POD、MDA、HO、EL），4 个表现出负向效应（SV、SFW、RL、CHC）。
我们发现，在干旱和对照条件下，只有一个参数在转基因和野生型植物之间的差异在 95%置信区间内具有统计学意义。在不同条件（干旱和正常）下，16 个参数中有 11 个 WRKY 过表达植物明显不同，这表明 WRKY 转录因子在植物对干旱胁迫的响应中发挥着重要作用。这些发现也为进一步研究 WRKY 转录因子在调节植物对环境胁迫的响应中的作用提供了理论依据。
