褪黑素调节烟草丁香假单胞菌抗性的功能研究  

Functional Analysis of Melatonin in the Regulation of Tobacco Plants Resistance to Pseudomonas syringae

作　　者：蔡楠 马文娜 肖林 张佳蓉 宋中邦[3] 陈奇[1] CAI Nan;MA Wenna;XIAO Lin;ZHANG Jiarong;SONG Zhongbang;CHEN Qi(Faculty of Life Science and Technology,Kunming University of Science and Technology,Kunming 650500,China;Yunnan Modern Vocational and Technical College,Chuxiong,Yunnan 675000,China;Yunnan Academy of Tobacco Agricultural Science,Kunming 650021,China)

机构地区：[1]昆明理工大学生命科学与技术学院,昆明650500 [2]云南现代职业技术学院,云南楚雄675000 [3]云南省烟草农业科学研究院,昆明650021

出　　处：《西北植物学报》2023年第6期948-955,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：云南省杰出青年基金项目(202201AV070008);云南省重点项目(202101AS070027)。

摘　　要：为分析褪黑素(N-乙酰-5-甲氧基色胺)在植物先天免疫中的功能及调控机理,研究以病原菌丁香假单胞杆菌(Pseudomonas syringae pv.tomato DC3000,Pst DC3000)—烟草互作系统为模型,检测了病原菌侵染对烟草褪黑素相关基因表达的影响,并探讨了褪黑素对植物叶片病原菌生长以及气孔开度和活性氧自由基(reactive oxygen species,ROS)含量的影响以及调控机理。结果表明:(1)Pst DC3000处理提高了烟草褪黑素合成(NtSNAT1)和受体(NtPMTR1)基因表达,且外源褪黑素处理降低了叶片中的病原菌含量。(2)与野生型植物相比,过表达大豆GmSNAT1基因显著提高了转基因烟草中内源褪黑素含量和NtPMTR1的表达,且转基因烟草叶片中的Pst DC3000菌落数显著下降。(3)外源褪黑素和细菌鞭毛蛋白多肽flg22处理诱导了野生型和转基因烟草保卫细胞中ROS产生和气孔关闭,且转基因植物对褪黑素和flg22诱导的气孔关闭和ROS产生比野生型烟草更加敏感。综上所述,研究表明褪黑素可能通过受体NtPMTR1介导的信号途径促进保卫细胞ROS产生,诱导气孔关闭,从而降低病原菌Pst DC3000的入侵。To analyze the function and regulatory mechanism of melatonin(N-acetyl-5-methoxytryptamine)in plant innate immunity,this study used the interaction between the pathogenic bacterium Pseudomonas syringae pv.tomato DC3000(Pst DC3000)and tobacco as a model system.The study examined the influence of pathogen invasion on the expression of tobacco genes related to melatonin and analyzed the effects and regulatory mechanisms of melatonin on pathogen grwoth,stomatal aperture,and ROS(reactive oxygen species)content in plant leaves.The results showed that:(1)Pst DC3000 treatment increased the expression of tobacco melatonin biosynthesis(NtSNAT1)and receptor(NtPMTR1)genes,and exogenous melatonin treatment reduced the bacterial contents in plant leaves.(2)Overexpression of the soybean GmSNAT1 significantly increased the endogenous melatonin concentrations and expression of NtPMTR1 in transgenic tobacco plants GmSNAT1-OE2 and GmSNAT1-OE5,and the Pst DC3000 bacteria growth number was significantly decreased.(3)Exogenous melatonin and bacterial flagellin peptide flg22 treatments induced the production of ROS and stomatal closure in both wild-type and transgenic tobacco guard cells,and the transgenic plants were more sensitive to melatonin-and flg22-induced stomatal closure and ROS production than the wild-type plants.Taken together,this study found that melatonin could reduce the bacteria invasion,which may probably be associated with promoting ROS production in guard cells and inducing stomatal closure via NtPMTR1-mediated signaling pathway.

关 键 词：植物褪黑素 ROS 气孔免疫 病原菌抗性 烟草 

分 类 号：S572[农业科学—烟草工业] S436.8[农业科学—作物学]