Weed Research Laboratory, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, People's Republic of China.
Australian Herbicide Resistance Initiative (AHRI), School of Agriculture and Environment, University of Western Australia, Crawley, Perth, Western Australia 6009, Australia.
J Agric Food Chem. 2023 Jun 21;71(24):9302-9313. doi: 10.1021/acs.jafc.3c01231. Epub 2023 May 11.
A wild radish population (R) has been recently confirmed to be cross-resistant to 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides without previous exposure to these herbicides. This cross-resistance is endowed by enhanced metabolism. Our study identified one 2-oxoglutarate/Fe(II)-dependent dioxygenase gene () and two P450 genes ( and ), which were significantly more highly expressed in R versus susceptible (S) plants. Gene functional characterization using transformation showed that overexpression of conferred a modest level of resistance to mesotrione. Ultra-performance liquid chromatography-tandem mass spectrometry analysis showed that tissue mesotrione levels in RrCYP709B1 transgenic plants were significantly lower than that in the wild type. In addition, overexpression of or in endowed resistance to tembotrione and isoxaflutole. Structural modeling indicated that mesotrione can bind to CYP709B1 and be easily hydroxylated to form 4-OH-mesotrione. Although each gene confers a modest level of resistance, overexpression of the multiple herbicide-metabolizing genes could contribute to HPPD-inhibiting herbicide resistance in this wild radish population.
最近证实，一个野萝卜种群（R）对 4-羟基苯基丙酮酸双加氧酶（HPPD）抑制剂除草剂具有交叉抗性，而此前并未接触过这些除草剂。这种交叉抗性是由增强的代谢赋予的。我们的研究鉴定了一个 2-氧代戊二酸/Fe(II)-依赖性双加氧酶基因（）和两个 P450 基因（和），它们在 R 相对于敏感（S）植物中的表达显著更高。使用 转化进行基因功能表征表明，过表达 赋予了对 mesotrione 的中等水平抗性。超高效液相色谱-串联质谱分析表明，RrCYP709B1 转基因 植物组织中的 mesotrione 水平明显低于野生型。此外，过表达 或 赋予了对 tembotrione 和 isoxaflutole 的抗性。结构建模表明，mesotrione 可以与 CYP709B1 结合，并且很容易被羟化为形成 4-OH-mesotrione。尽管每个基因赋予了中等水平的抗性，但多种除草剂代谢基因的过表达可能有助于这种野萝卜种群对 HPPD 抑制剂除草剂的抗性。
