Salicylic acid (SA) is an essential hormone for plant immune responses. In Arabidopsis, SA is perceived by two groups of receptors, NPR1 and NPR3/4, which play opposite roles in regulating defence gene expression. How SA binds to its receptors is now revealed by crystal structure analysis.

中文翻译：

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水杨酸感知的结构视图。

水杨酸（SA）是植物免疫反应所必需的激素。在拟南芥中，SA被两组受体NPR1和NPR3 / 4感知，它们在调节防御基因表达中起相反的作用。现在，通过晶体结构分析揭示了SA如何与其受体结合。