PDF(Pubmed)
Abstract：
Although thaumatin-like proteins (TLPs) are involved in resistance to a variety of fungal diseases, whether the TLP5 and TLP6 genes in tomato plants (Solanum lycopersicum) confer resistance to the pathogenesis of soil-borne diseases has not been demonstrated. In this study, five soil-borne diseases (fungal pathogens: Fusarium solani, Fusarium oxysporum, and Verticillium dahliae; bacterial pathogens: Clavibacter michiganense subsp. michiganense and Ralstonia solanacearum) were used to infect susceptible \"No. 5\" and disease-resistant \"S-55\" tomato cultivars. We found that SlTLP5 and SlTLP6 transcript levels were higher in susceptible cultivars treated with the three fungal pathogens than in those treated with the two bacterial pathogens and that transcript levels varied depending on the pathogen. Moreover, the SlTLP5 and SlTLP6 transcript levels were much higher in disease-resistant cultivars than in disease-susceptible cultivars, and the SlTLP5 and SlTLP6 transcript levels were higher in cultivars treated with the same fungal pathogen than in those treated with bacterial pathogens. SlTLP6 transcript levels were higher than SlTLP5. SlTLP5 and SlTLP6 overexpression and gene-edited transgenic mutants were generated in both susceptible and resistant cultivars. Overexpression and knockout increased and decreased resistance to the five diseases, respectively. Transgenic plants overexpressing SlTLP5 and SlTLP6 inhibited the activities of peroxidase (POD), superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) after inoculation with fungal pathogens, and the activities of POD, SOD, and APX were similar to those of fungi after infection with bacterial pathogens. The activities of CAT were increased, and the activity of β-1,3-glucanase was increased in both the fungal and bacterial treatments. Overexpressed plants were more resistant than the control plants. After SlTLP5 and SlTLP6 knockout plants were inoculated, POD, SOD, and APX had no significant changes, but CAT activity increased and decreased significantly after the fungal and bacterial treatments, contrary to overexpression. The activity of β-1,3-glucanase decreased in the treatment of the five pathogens, and the knocked-out plants were more susceptible to disease than the control. In summary, this study contributes to the further understanding of TLP disease resistance mechanisms in tomato plants.
摘要：
尽管Thaumatin样蛋白（TLPs）参与了对多种真菌疾病的抗性，尚未证明番茄植物（Solanumlycopersicum）中的TLP5和TLP6基因是否赋予对土壤传播疾病的发病机理的抗性。在这项研究中,五种土壤传播疾病(真菌病原体：镰刀菌，尖孢镰刀菌,和黄萎病菌；细菌病原体：麦卡威杆菌亚种。密歇根和青枯雷尔氏菌）被用于感染易感的\“No.5"和抗病\"S-55\"番茄品种。我们发现，用三种真菌病原体处理的易感品种中的SlTLP5和SlTLP6转录水平高于用两种细菌病原体处理的品种，并且转录水平因病原体而异。此外，抗病品种的SlTLP5和SlTLP6转录水平远高于疾病易感品种，用相同真菌病原体处理的品种的SlTLP5和SlTLP6转录水平高于用细菌病原体处理的品种。SlTLP6转录物水平高于SlTLP5。在易感和抗性品种中均产生了SlTLP5和SlTLP6过表达和基因编辑的转基因突变体。过表达和基因敲除增加和降低对五种疾病的抗性，分别。过表达SlTLP5和SlTLP6的转基因植物抑制过氧化物酶（POD）的活性，超氧化物歧化酶（SOD），抗坏血酸过氧化物酶（APX），和过氧化氢酶（CAT）接种真菌病原体后，以及POD的活动，SOD,APX与细菌病原体感染后的真菌相似。禁止酷刑委员会的活动有所增加，在真菌和细菌处理中，β-1,3-葡聚糖酶的活性均增加。过表达植物比对照植物更具抗性。在SlTLP5和SlTLP6敲除的植物接种后，POD,SOD,APX没有显著变化，但CAT活性在真菌和细菌处理后显著增加和下降，与过度表达相反。β-1,3-葡聚糖酶活性在五种病原体的治疗中降低,敲除的植物比对照植物更容易患病。总之,本研究有助于进一步了解番茄植株的TLP抗病性机制。
