Silencing JA hydroxylases in Nicotiana attenuata enhances jasmonic acid-isoleucine-mediated defenses against Spodoptera litura

作     者：Jinxiang Tang Dahai Yang Jianqiang Wu Suiyun Chen Lei Wang Jinxiang Tang;Dahai Yang;Jianqiang Wu;Suiyun Chen;Lei Wang

作者机构：Department of Economic Plants and BiotechnologyYunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming650201China Tobacco Breeding and Biotechnology Research CenterYunnan Academy of Tobacco Agricultural SciencesKey Laboratory of Tobacco Biotechnological BreedingNational Tobacco Genetic Engineering Research CenterKunming650021China School of Life ScienceYunnan UniversityKunming650091China 

出 版 物：《Plant Diversity》 (植物多样性（英文版）)

年 卷 期：2020年第42卷第2期

页      面：111-119页

核心收录：

学科分类：0710[理学-生物学] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 09[农学] 0904[农学-植物保护] 090401[农学-植物病理学] 0901[农学-作物学] 0902[农学-园艺学] 0713[理学-生态学] 

基　　金：supported by the Key Project of Applied Basic Research Program of Yunnan(2017FA015) the Young Academic and Technical Leader Raising Foundation of Yunnan Province(no. 2017HB063) the Yunnan Academy of Tobacco Agricultural Sciences(2018530000241002 and 2019530000241003) the Biotechnology Experimental Center at the Kunming Institute of Botany,CAS,for supporting plant cultivation. 

主　　题：JA metabolism 12-OH-JA Spodoptera litura 2-Oxoglutarate oxygenase Herbivore defense Nicotiana attenuata 

摘      要：Jasmonic acid(JA)plays important roles in plant resistance to insect herbivores.One important derivative of JA is 12-OH-JA,which is produced by two independent pathways:direct hydroxylation of JA by jasmonate-induced oxygenases(JOXs)or hydrolyzation of 12-OH-JA-Ile.Yet the function of 12-OH-JA in plant-herbivore interactions remains largely unknown.In this study,we silenced four JOX homologs independently in the wild tobacco Nicotiana attenuata by virus-induced gene silencing(VIGS),and found that all four JOX homologs are involved in JA hydroxylation.Simultaneously silencing the four JA hydroxylases in VIGS-NaJOXs plants decreased herbivory-induced 12-OH-JA by 33%,but JA and JA-Ile levels increased by 45%and 30%,respectively,compared to those in control plants.Compared to direct hydroxylation from JA,hydrolyzation from 12-OH-JA-Ile is equally important for herbivory-induced 12-OHJA accumulation:in the 12-OH-JA-Ile deficient irJAR4/6 plants,12-OH-JA decreased 34%.Moreover,VIGSNaJOXs plants exhibited enhanced resistance to the generalist herbivore Spodoptera litura.The poor larval performance was strongly correlated with high levels of several JA-Ile-dependent direct defense metabolites in the VIGS-NaJOXs plants.When we simultaneously silenced all four JA hydroxylases in the JAIle-deficient irJAR4/6 background,the enhanced herbivore resistance diminished,demonstrating that enhanced herbivore resistance resulted from elevated JA-Ile levels.Given that silencing these NaJOX-like genes did not detectably alter plant growth but highly increased plant defense levels,we propose that JOX genes are potential targets for genetic improvement of herbivore-resistant crops.