清华大学刘玉乐研究组揭示甲基水杨酸介导的植物空气防御(AD)的分子基础。2023年9月13日出版的《自然》杂志发表了这项成果。

本文揭示了水杨酸甲酯(MeSA)、水杨酸结合蛋白-2 (SABP2)、转录因子NAC2和水杨酸羧甲基转移酶-1 (SAMT1)形成一个信号通路，介导AD对抗蚜虫和病毒。空气中的MeSA被邻近植物中的SABP2感知并转化为水杨酸。然后水杨酸引起信号转导级联，激活NAC2-SAMT1模块进行MeSA生物合成，诱导植物抗蚜免疫，减少病毒传播。

为了抵消这一点，一些蚜虫传播的病毒编码含有解旋酶的蛋白质，通过与NAC2相互作用来抑制AD，使NAC2亚细胞重定位和不稳定。因此，植物对蚜虫的排斥程度降低，更适合蚜虫的生存、侵染和病毒传播。他们的发现揭示了AD和蚜虫-病毒共同进化的机制基础，证明AD是一种潜在的生物激励策略来控制蚜虫和病毒。

研究人员表示，蚜虫传播病毒，是破坏性的农作物害虫。被蚜虫攻击的植物释放挥发性化合物，在邻近植物中引发AD。然而，AD的发病机制尚不清楚。

附：英文原文

Title: Molecular basis of methyl-salicylate-mediated plant airborne defence

Author: Gong, Qian, Wang, Yunjing, He, Linfang, Huang, Fan, Zhang, Danfeng, Wang, Yan, Wei, Xiang, Han, Meng, Deng, Haiteng, Luo, Lan, Cui, Feng, Hong, Yiguo, Liu, Yule

Issue&Volume: 2023-09-13

Abstract: Aphids transmit viruses and are destructive crop pests1. Plants that have been attacked by aphids release volatile compounds to elicit airborne defence (AD) in neighbouring plants2–5. However, the mechanism underlying AD is unclear. Here we reveal that methyl-salicylate (MeSA), salicylic acid-binding protein-2 (SABP2), the transcription factor NAC2 and salicylic acid-carboxylmethyltransferase-1 (SAMT1) form a signalling circuit to mediate AD against aphids and viruses. Airborne MeSA is perceived and converted into salicylic acid by SABP2 in neighbouring plants. Salicylic acid then causes a signal transduction cascade to activate the NAC2–SAMT1 module for MeSA biosynthesis to induce plant anti-aphid immunity and reduce virus transmission. To counteract this, some aphid-transmitted viruses encode helicase-containing proteins to suppress AD by interacting with NAC2 to subcellularly relocalize and destabilize NAC2. As a consequence, plants become less repellent to aphids, and more suitable for aphid survival, infestation and viral transmission. Our findings uncover the mechanistic basis of AD and an aphid–virus co-evolutionary mutualism, demonstrating AD as a potential bioinspired strategy to control aphids and viruses. Aphid-transmitted viruses encode proteins that suppress the plant airborne defence response—which is triggered by volatile chemicals released by neighbouring plants after aphid attack—and the plants consequently become less repellent to aphids and more suitable for aphid survival, infestation and viral transmission.

DOI: 10.1038/s41586-023-06533-3

Source: https://www.nature.com/articles/s41586-023-06533-3