Huang Huang, Zhao Wenchao, Qiao Hui, Li Chonghua, Sun Lulu, Yang Rui, Ma Xuechun, Ma Jilin, Song Susheng, Wang Shaohui
Plant Science and Technology College, Beijing University of Agriculture, Beijing, 102206, China.
Beijing Key Laboratory for Agricultural Application and New Technique, Beijing University of Agriculture, Beijing, 102206, China.
Hortic Res. 2022 Sep 5;9:uhac197. doi: 10.1093/hr/uhac197. eCollection 2022.
Parasitic root-knot nematodes (RKNs) cause a severe reduction in crop yield and seriously threaten agricultural production. The phytohormones jasmonates (JAs) are important signals regulating resistance to multiple biotic and abiotic stresses. However, the molecular mechanism for JAs-regulated defense against RKNs in tomato remains largely unclear. In this study, we found that the transcription factor SlWRKY45 interacted with most JA-ZIM domain family proteins (JAZs), key repressors of the JA signaling. After infection by the RKN , the mutants exhibited lower gall numbers and egg numbers per gram of roots than wild type, whereas overexpression of attenuated resistance to . Under infection, the contents of jasmonic acid (JA) and JA-isoleucine (JA-Ile) in roots were repressed by overexpression. Furthermore, SlWRKY45 bound to and inhibited the promoter of the JA biosynthesis gene (), and repressed its expression. Overall, our findings revealed that the SlJAZ-interaction protein SlWRKY45 attenuated RKN-regulated JA biosynthesis and repressed defense against the RKN in tomato.
寄生性根结线虫（RKNs）会导致作物产量严重下降，并严重威胁农业生产。植物激素茉莉酸（JAs）是调节对多种生物和非生物胁迫抗性的重要信号。然而，JAs调控番茄对RKNs防御的分子机制仍不清楚。在本研究中，我们发现转录因子SlWRKY45与茉莉酸-ZIM结构域家族蛋白（JAZs）（茉莉酸信号的关键抑制因子）相互作用。在被RKNs感染后，突变体每克根上的虫瘿数和卵数比野生型少，而SlWRKY45的过表达减弱了对RKNs的抗性。在RKNs感染下，根中茉莉酸（JA）和茉莉酸异亮氨酸（JA-Ile）的含量因过表达而受到抑制。此外，SlWRKY45与茉莉酸生物合成基因的启动子结合并抑制其表达。总体而言，我们的研究结果表明，与SlJAZ相互作用的蛋白SlWRKY45减弱了RKNs调控的茉莉酸生物合成，并抑制了番茄对RKNs的防御。
