Zhang Huangwei, Jin Peiyuan, Kong Yixuan, Jia Chenchen, Qiao Panpan, Dong Yinglu, Zhou Yuxin, Hu Jian, Yang Zhimin, Jung Geunhwa
College of Agro-grassland Science, Nanjing Agricultural University, Nanjing 210095, China.
Stockbridge School of Agriculture, University of Massachusetts, Amherst, Massachusetts 01003, United States.
J Agric Food Chem. 2024 Oct 1. doi: 10.1021/acs.jafc.4c05106.
Recently, has emerged as a significant pathogen threatening turfgrass, and its escalating resistance to multiple drugs often undermines field interventions. This study highlighted the critical role of the fungus-specific transcription factor CjXDR1 (formerly ShXDR1) in regulating multidrug resistance (MDR) in . This was demonstrated through experiments involving CjXDR1-knockout and CjXDR1-complemented strains. Our sequence analysis revealed five mutations in CjXDR1: G445D, K453E, S607F, D676H, and V690A. All five gain-of-function (GOF) mutations were confirmed to directly contribute to MDR against three different classes of fungicides (propiconazole: demethylation inhibitor, boscalid: succinate dehydrogenase inhibitor, and iprodione: dicarboximide) using the genetic transformation system and in vitro fungicide-sensitivity assay. Comparative transcriptome analysis revealed that CjXDR1 and its GOF mutations led to the overexpression of downstream genes encoding a Phase I metabolizing enzyme () and two Phase III transporters ( and ) previously reported. Knockout mutants of CYP68, CjPDR1, CjAtrD, and double-knockout mutants of CjPDR1 and CjAtrD exhibited increased sensitivity to all three fungicides tested. Among these, the CYP68-knockout mutants displayed the highest sensitivity to propiconazole, while the CjPDR1 knockout mutant exhibited significantly increased sensitivity to all three fungicides. Double-knockout mutants of CjPDR1 and CjAtrD displayed greater sensitivity than the single knockouts. In conclusion, multiple GOF mutants in CjXDR1 contribute to MDR by upregulating the expression of , , and . This study enhances our understanding of the molecular mechanisms underlying MDR in plant pathogenic fungi, providing valuable insights into GOF mutation structures and advancing the development of antifungal drugs.
最近，[病原体名称未给出]已成为威胁草坪草的一种重要病原体，其对多种药物的耐药性不断增强，常常破坏田间干预措施。本研究强调了真菌特异性转录因子CjXDR1（原ShXDR1）在调节[病原体名称未给出]的多药耐药性（MDR）中的关键作用。这通过涉及CjXDR1基因敲除和CjXDR1互补菌株的实验得到了证明。我们的序列分析揭示了CjXDR1中的五个突变：G445D、K453E、S607F、D676H和V690A。使用遗传转化系统和体外杀菌剂敏感性测定，证实所有这五个功能获得性（GOF）突变直接导致对三种不同类别的杀菌剂（丙环唑：脱甲基抑制剂、啶酰菌胺：琥珀酸脱氢酶抑制剂和异菌脲：二甲酰亚胺）的多药耐药性。比较转录组分析表明，CjXDR1及其GOF突变导致先前报道的编码I相代谢酶（[酶名称未给出]）和两种III相转运蛋白（[转运蛋白名称未给出]和[转运蛋白名称未给出]）的下游基因的过表达。CYP68、CjPDR1、CjAtrD的基因敲除突变体以及CjPDR1和CjAtrD的双基因敲除突变体对所有三种测试杀菌剂的敏感性均增加。其中，CYP68基因敲除突变体对丙环唑的敏感性最高，而CjPDR1基因敲除突变体对所有三种杀菌剂的敏感性均显著增加。CjPDR1和CjAtrD的双基因敲除突变体比单基因敲除突变体表现出更高的敏感性。总之，CjXDR1中的多个GOF突变通过上调[酶名称未给出]、[转运蛋白名称未给出]和[转运蛋白名称未给出]的表达来促进多药耐药性。本研究增进了我们对植物病原真菌多药耐药性分子机制的理解，为GOF突变结构提供了有价值的见解，并推动了抗真菌药物的开发。
