Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland Brisbane, QLD, Australia ; Bioengineering College, Chongqing University Chongqing, China.
Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland Brisbane, QLD, Australia.
Front Chem. 2015 Jan 20;3:1. doi: 10.3389/fchem.2015.00001. eCollection 2015.
Fusarium oxysporum is a devastating pathogen causing extensive yield losses in a variety of crops and development of sustainable, environmentally friendly methods to improve crop resistance is crucial. We have used Host-Delivered RNA interference (HD-RNAi) technology to partially silence three different genes (FOW2, FRP1, and OPR) in the hemi-biotrophic fungus F. oxysporum f. sp. conglutinans. Expression of double stranded RNA (dsRNA) molecules targeting fungal pathogen genes was achieved in a number of transgenic Arabidopsis lines. F. oxysporum infecting the transgenic lines displayed substantially reduced mRNA levels on all three targeted genes, with an average of 75, 83, and 72% reduction for FOW2, FRP1, and OPR, respectively. The silencing of pathogen genes had a clear positive effect on the ability of the transgenic lines to fight infection. All transgenic lines displayed enhanced resistance to F. oxysporum with delayed disease symptom development, especially FRP1 and OPR lines. Survival rates after fungal infection were higher in the transgenic lines compared to control wild type plants which consistently showed survival rates of 10%, with FOW2 lines showing 25% survival; FRP1 lines 30-50% survival and OPR between 45 and 70% survival. The down-regulation effect was specific for the targeted genes without unintended effects in related genes. In addition to producing resistant crops, HD-RNAi can provide a useful tool to rapidly screen candidate fungal pathogenicity genes without the need to produce fungal knockout mutants.
尖孢镰刀菌是一种破坏性病原体，可导致多种作物的广泛减产，因此开发可持续的、环保的方法来提高作物抗性至关重要。我们使用宿主递呈 RNA 干扰（HD-RNAi）技术部分沉默半生物营养真菌尖孢镰刀菌 f. sp. conglutinans 中的三个不同基因（FOW2、FRP1 和 OPR）。靶向真菌病原体基因的双链 RNA（dsRNA）分子的表达在许多转基因拟南芥品系中得以实现。感染转基因系的尖孢镰刀菌显示出所有三个靶向基因的 mRNA 水平显著降低，FOW2、FRP1 和 OPR 的平均降低分别为 75%、83%和 72%。病原体基因的沉默对转基因系抵抗感染的能力有明显的积极影响。所有转基因系对尖孢镰刀菌的抗性均增强，发病症状发展延迟，尤其是 FRP1 和 OPR 系。与对照野生型植物相比，转基因系在真菌感染后的存活率更高，野生型植物的存活率始终为 10%，FOW2 系的存活率为 25%；FRP1 系为 30-50%，OPR 系为 45-70%。下调效应是针对靶向基因的，而对相关基因没有意外影响。除了产生抗性作物外，HD-RNAi 还可以提供一种有用的工具，用于快速筛选候选真菌致病性基因，而无需产生真菌敲除突变体。
