番茄SlWRKY80基因共抑制表达影响转基因植株抗逆性的研究

Cosuppression of SlWRKY80 resulted in affected defense ability against stresses

利用植物基因工程技术,构建了植物表达载体pBI121-35S::SlWRKY80,并利用根癌农杆菌介导法转化番茄,得到转基因阳性植株.通过生物信息学分析SlWRKY80蛋白序列与9种物种进行同源比对,发现高度保守的WRKY结构域和C2HC型锌指结构.采用Real-Time PCR分析转基因植株中SlWRKY80mRNA的表达情况,结果显示SlWRKY80的表达量显著下调,出现共抑制现象.用不同浓度的NaCl对转基因种子和野生型种子进行胁迫处理,结果显示在NaCl浓度为100mM和150mM时,转基因幼苗初生根的长度与野生型相比相对较短,显示SlWRKY80对初生根的生长有促进作用;用Pto DC3000接种转基因植株和野生型植株叶片,结果显示野生型植株叶片中细菌增殖率是转基因植株叶片中的2.5倍,显示SlWRKY80在番茄抗病信号转导中扮演负调控作用.

Using plant genetic engineering technology, plant-expression vector pBI121-35S：： SlWRKY80 was constructed. The recombinant plasmid was introduced into tomato genome using Agrobacterium tumefaciens-mediated transformation. Bioinformatic analysis showed SIWRKY80 had one conserved WRKY domain and C2 HC zinc-finger. The analysis of real time PCR revealed a distinct reduction of SI- WRKY80 expression levels in the transgenic lines compared to that of wild plants,which means co-sup- pression appeared. Seeds of wild type and transgenic plants were treated with different concentrations of NaC1. The results showed that the primary root length of transgenic seedlings were shorter than that of wild-type, suggesting that the SIWRKY80 play an important role in the growth of plant primary root. We inoculated leaves of transgenie and wild-type plants with Pto DC3000. The result showed that the bacteria proliferation rate of wild-type leaves was 2.5 times as that of transgenic plants, suggesting that SIWRKYSO acts as a negative regulator in the tomato signal transduetion of disease resistance.