Lan Xingjie, Wang Xiaoxia, Tao Quandan, Zhang Haotian, Li Jinyang, Meng Yuling, Shan Weixing
State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Xianyang 712100, China.
College of Plant Protection, Northwest A&F University, Xianyang 712100, China.
Plants (Basel). 2022 Mar 24;11(7):858. doi: 10.3390/plants11070858.
Nonhost resistance refers to resistance of a plant species to all genetic variants of a non-adapted pathogen. Such resistance has the potential to become broad-spectrum and durable crop disease resistance. We previously employed and a forward genetics approach to identify plant mutants susceptible to the nonhost pathogen , which resulted in identification of the T-DNA insertion mutant (). In this study, we report the identification of VQ motif-containing protein 28 (), whose expression was highly up-regulated in the mutant . Stable transgenic plants constitutively overexpressing compromised nonhost resistance (NHR) against and , and supported increased infection of . Transcriptomic analysis showed that overexpression of resulted in six differentially expressed genes (DEGs) that are involved in the response to abscisic acid (ABA). High performance liquid chromatography-mass spectrometry (HPLC-MS) detection showed that the contents of endogenous ABA, salicylic acid (SA), and jasmonate (JA) were enriched in overexpression lines. These findings suggest that overexpression of may lead to an imbalance in plant hormone homeostasis. Furthermore, transient overexpression of in rendered plants more susceptible to pathogens. Deletion mutant analysis showed that the C-terminus and VQ-motif were essential for plant susceptibility. Taken together, our results suggest that negatively regulates plant NHR to pathogens.
非寄主抗性是指植物物种对非适应性病原菌的所有遗传变异体的抗性。这种抗性有可能成为广谱且持久的作物抗病性。我们之前采用正向遗传学方法来鉴定对非寄主病原菌敏感的植物突变体，这导致了T-DNA插入突变体（）的鉴定。在本研究中，我们报告了含VQ基序蛋白28（）的鉴定，其在突变体中的表达高度上调。组成型过表达的稳定转基因植物对和的非寄主抗性（NHR）受损，并支持的感染增加。转录组分析表明，的过表达导致六个参与脱落酸（ABA）应答的差异表达基因（DEGs）。高效液相色谱-质谱联用（HPLC-MS）检测表明，内源ABA、水杨酸（SA）和茉莉酸（JA）的含量在过表达株系中富集。这些发现表明，的过表达可能导致植物激素稳态失衡。此外，在中瞬时过表达使植物对病原菌更敏感。缺失突变体分析表明，C末端和VQ基序对植物易感性至关重要。综上所述，我们的结果表明负调控植物对病原菌的NHR。
