Cheng Xi, Tian Cai-Juan, Li Ai-Ning, Qiu Jin-Long
Institute of Microbiology, Chinese Academy of Science, Beijing, China.
Yi Chuan. 2012 Feb;34(2):134-44. doi: 10.3724/sp.j.1005.2012.00134.
Plants have established a complicated immune defense system during co-evolution with pathogens. The innate immune system of plants can be generally divided into two levels. One, named PAMP-triggered immunity (PTI), is based on the recognition of pathogen-associated molecular patterns by pattern-recognition receptors, which confers resistance to most pathogenic microbes. The other begins in cytoplasm and mainly relies on recognition of microbial effectors by plant resistance proteins in direct or indirect ways, which then initiates potent defense responses. This process, termed effector-triggered immunity (ETI), is necessary for defense against pathogens that can secret effectors to suppress the first level of immunity. Activation of these two layers of immunity in plant is based on distinguishing and recognition of "self" and "non-self" signals. Recognition of "non-self" signals can activate signal cascades, such as MAPK cascades, which will then induce defense gene expression and corresponding defense responses. In this review, we focused on underlying molecular mechanisms of plant-pathogen interactions and the latest advances of the PTI and ETI signaling network.
在与病原体共同进化的过程中,植物建立了复杂的免疫防御系统。植物的固有免疫系统通常可分为两个层次。一个称为病原体相关分子模式触发的免疫(PTI),它基于模式识别受体对病原体相关分子模式的识别,赋予植物对大多数致病微生物的抗性。另一个始于细胞质,主要依赖植物抗性蛋白直接或间接识别微生物效应子,进而引发强烈的防御反应。这个过程称为效应子触发的免疫(ETI),对于抵御能够分泌效应子以抑制第一层免疫的病原体来说是必要的。植物中这两层免疫的激活基于对“自我”和“非自我”信号的区分与识别。对“非自我”信号的识别能够激活信号级联反应,如丝裂原活化蛋白激酶(MAPK)级联反应,进而诱导防御基因表达及相应的防御反应。在本综述中,我们重点关注了植物 - 病原体相互作用的潜在分子机制以及PTI和ETI信号网络的最新进展。