OsGLO1调控水稻抗稻瘟病的机制研究  

Research on the mechanism of OsGLO1 regulating rice blast resistance

作　　者：李娇 圣聪 李涛[1] 喻晗晞 李绚 赵弘巍[1] LI Jiao;SHENG Cong;LI Tao;YU Hanxi;LI Xuan;ZHAO Hongwei(College of Plant Protection/Laboratory of Bio-interactions and Crop Health,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学植物保护学院/生物互作与作物健康重点实验室,江苏南京210095

出　　处：《南京农业大学学报》2022年第1期64-71,共8页Journal of Nanjing Agricultural University

基　　金：国家自然科学基金项目(31872040);中央高校基本科研业务费专项资金(JCQY201904)。

摘　　要：[目的]水稻乙醇酸氧化酶1(OsGLO1)是光呼吸中的关键酶,调控植物免疫信号分子过氧化氢(H_(2)O_(2))的产生。本研究旨在分析OsGLO1在稻瘟病抗性中的功能,揭示其调控机制。[方法]利用稻瘟病菌株Guy11分别侵染水稻野生型(ZH11)和OsGLO1基因过表达(OsGLO1-OE)以及沉默(cas9-glo1)的转基因水稻,观察抗病性表型,确定OsGLO1对抗病性的影响。使用稻瘟病菌GZ1(GFP标记)侵染水稻,比较菌丝扩增差异,明确OsGLO1抑制稻瘟病菌侵染后扩展的能力。分别通过定性和定量试验观察和分析H_(2)O_(2)的积累位点和积累量,研究OsGLO1在PTI途径中的作用;通过RT-PCR检测水杨酸(SA)和茉莉酸(JA)信号通路相关防御基因的表达水平,探明OsGLO1对激素信号途径的影响。[结果]与野生型相比,受Guy11侵染的OsGLO1-OE水稻病斑更小,相对真菌生长量显著降低,附着胞以及侵染菌丝周围的活性氧积累增多,叶片中H_(2)O_(2)含量显著升高;而cas9-glo1在病斑面积和真菌生物量等方面明显高于野生型,被侵染叶片表面附着胞周围活性氧积累无显著变化,侵染菌丝周围的活性氧积累减少,叶片中H_(2)O_(2)含量显著降低。GZ1侵染48 h后,荧光显微观察显示,OsGLO1-OE水稻叶鞘中的稻瘟病菌侵染程度比野生型明显减弱,而cas9-glo1叶鞘中的稻瘟病菌侵染程度比野生型明显增强。OsGLO1过表达能显著提高SA信号途径的防卫基因(如OsPR1a和OsEDS1)的表达水平,但是对JA信号通路基因的表达没有明显影响。[结论]OsGLO1可以通过激活SA信号通路正向调控水稻对稻瘟病的抗病性。[Objectives]Rice glycolate oxidase 1(OsGLO1)is a key enzyme in photorespiration,which can regulate the production of plant immune signal molecule hydrogen peroxide(H_(2)O_(2)).The purpose of this study was to analyze the function of OsGLO1 in rice blast resistance and reveal its regulatory mechanism.[Methods]Wild-type(ZH11),OsGLO1 gene overexpression(OsGLO1-OE)and silencing mutant(cas9-glo1)rice lines were challenged with Magnaporthe oryzae strains.Rice leaves were inoculated with the blast strain Guy11 so that varied resistant phenotypes could be characterized.Rice leaf sheath was inoculated with the blast strain GZ1(eGFP-tagged)so that fungal hyphae penetration ability could be examined.Tissues were observed and analyzed through qualitative and quantitative experiments respectively so that H_(2)O_(2) accumulation position and amount were recorded.The expression of salicylic acid(SA)and jasmonic acid(JA)signaling pathway genes were compared so that involvement of these phytohormones could be assessed.[Results]After Guy11 infection,it was found that OsGLO1-OE exhibited significantly smaller lesions,reduced relative fungal growth,increased ROS accumulation around the appressorium as well as the invasive hyphae,and H_(2)O_(2) content in the leaves significantly increased more than that in the wild type.In contrast,cas9-glo1 demonstrated significantly larger lesions and higher fungal biomass than that in the wild type.ROS accumulation around the appressorium on the surface of infected cas9-glo1 leaves did not change significantly,but ROS accumulation around the invasive hyphae was reduced,and H_(2)O_(2) content in the leaves significantly decreased.After 48 h GZ1 infection,OsGLO1-OE leaf sheath exhibited significantly weaker fungal hyphae development compared with that in the wild type rice,while the hyphae development on the cas9-glo1 leaf sheath significantly increased compared with that in the wild type leaf sheath.In addition,overexpression of OsGLO1 significantly induced the expression of SA signaling pathway c

关 键 词：乙醇酸氧化酶 稻瘟病 抗病性 过氧化氢 水杨酸 

分 类 号：S412[农业科学—植物保护]