植物天然免疫系统研究进展

Recent advances in plant immune system

很多植物病原菌严重地损害植物的生长和繁殖。植物与病原体协同进化过程中,也逐渐形成了一系列复杂高效的保护机制来抵御病原物的侵染。植物中抵抗外界微生物刺激所形成的系统被称为植物天然免疫系统,可分为两个层次。第1个层次是植物模式识别受体(PRRs)识别病原相关分子模式(PAMPs),触发病原相关分子模式触发的免疫反应(PTI),激活植物体中促丝裂原活化蛋白激酶(MAPK)信号通路使植物产生早期应答反应。PTI适应性较广,可识别和响应包括非致病菌的许多类微生物。第2个层次是病原菌产生效应因子抑制基础免疫响应PTI,而植物产生针对性更强的抗性蛋白(R蛋白)识别效应因子,并通过效应因子触发型免疫(ETI)来重建植物的抗性。笔者综述了近年来植物天然免疫系统的研究进展,认为随着对植物天然免疫系统研究的深入,应重视PTI和ETI的结合利用,有效扩大植物抗菌谱,改良植物ETI抗性。

Many plant-associated microbes are pathogens that impair plant growth and reproduction. Plants have evolved a series of complicated defense mechanism against pathogens during their long term process of co-evolution. Plants innate immune system efficiently detects and wards off potentially dangerous microbes. A first layer of this system is based on sensitive perception of pathogen-or microbe-associated molecular patterns （PAMPs） through pattern recognition receptors （PRRs） at the plant＇s cell surface,which would active mitogen-activated protein kinase（MAPK） signaling cascade and burst early responses in plant resistance to pathogen attacks. The first layer recognizes and responds to many classes of microbes, including non-pathogens. With pathogens produce effectors to inhibit PTI, plants can perceive such effectors through additional receptors, typically nucleotide binding leucine-rich repeat （NB-LRR） proteins, to mount a second layer of defense called effect or triggered immunity （ETI）. Here, we highlight recent literature on plants innate immune system, and based on a detailed understanding of plant immune function, we should focus on the combination of the use of PTI and ETI to expand the antimicrobial spectrum of plant effectively and improve plants＇s disease-resistance.