病原体的侵染严重威胁了植物正常的生长发育, 是造成作物减产的主要因素之一。植物免疫系统在植物抵抗病原体侵染中发挥核心作用。自从2006年提出植物免疫系统主要由模式触发的免疫(PTI)和效应子触发的免疫(ETI)两层防御体系组成以来, 大量的研究工作聚焦于解析PTI和ETI中的关键受体/共受体、PTI和ETI信号通路的组分及其作用机制、植物免疫激素水杨酸和茉莉素的合成和信号转导, 逐步形成了以病原体识别、活性氧爆发、Ca²⁺内流、 MAPK级联信号转导以及下游防御基因的诱导表达为核心的复杂免疫调控网络。近几年的研究表明, 植物免疫相关基因的表达不仅受到转录调控, 其mRNA的稳定性、翻译效率和翻译产物也受到多种转录后调控机制的影响, 包括可变剪接、m⁶A修饰、小RNA、uORF和R-motif。该综述概述了植物免疫系统的组成和主要的调控通路及其组分, 详述了转录后调控对植物免疫的影响以及病原体对相关调控作用的干扰机制, 梳理了转录后调控作用元件在作物中的应用, 为保障粮食安全、提高作物的抗病性和分子育种的元件筛选方面提供了参考。

Pathogen infection is a serious threat to plant growth and development, causing severe crop yield reduction. The plant immune system, which is mainly composed of PTI (Pattern-triggered immunity) and ETI (Effector-triggered immunity), plays an essential role in resistance against pathogen infection. A large amount of research focused on resolving the key immune receptors/co-receptors, the components and regulation mechanisms of the PTI and ETI signaling pathways, and the biosynthesis and signaling pathways of the plant immune hormones salicylic acid and jasmonic acid. The major events during plant immune responses include pathogen recognition, the outburst of reactive oxygen species, Ca2+ influx, MAPK cascade signaling, and the induced expression of downstream defense genes. Recent studies have revealed that the expression of plant immune-related genes is not only regulated at the transcriptional level. The stability, translation efficiency, and translation products of their mRNAs are affected by a variety of post-transcriptional regulatory mechanisms, including alternative splicing, m6A modification, small RNAs, uORFs, and R-motifs. Here, we summarized the present understanding of the plant immune system and mainly introduced the latest studies of the post-transcriptional regulation of plant immunity. This review also covered some findings that showed how pathogen interferes with the host post-transcriptional regulatory machinery. Some post-transcriptional regulatory elements have been successfully applied in crops, providing new molecular tools to improve crop resistance to diseases and contribute to food security.