Yanjing Guo, Jiale Shi, Xia Wang-Zhu, Liru Mi, He Wang, Min Chen, Dan Cheng, Hongyu Ma, Bernal E Valverde, Yujing Liu, Matthew J Terry, Shiguo Chen
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引用次数: 0
Abstract
Necrotrophic Alternaria alternata induces EXECUTER 1(EX1)/2-dependent singlet oxygen (1O2) bursts, leading to plant cell death, with jasmonic acid (JA) acting as a key signal transducer downstream of EX1/2-mediated signaling. Salicylic acid (SA), a crucial defense hormone, is known to respond to pathogen invasion and activate defense gene expression. Previous studies emphasize the importance of SA in A. alternata-induced necrosis in the light of the increased susceptibility of SA-deficient transgenic Arabidopsis NahG to A. alternata. In this study, we investigated the role of SA in A. alternata-triggered 1O2 signaling in Arabidopsis. We found that EX1/2 deficiency did not alter SA levels in Arabidopsis infected with A. alternata, indicating that SA signaling regulates A. alternata-induced pathogenesis through an EX1/2-independent pathway. Exogenous SA application and increased endogenous SA in the ssi2-2 mutant enhanced resistance but inhibited JA production. Conversely, SA signaling deficiency in the eds1 and pad4 mutants increased susceptibility and elevated JA levels. In conclusion, SA enhances Arabidopsis defense against A. alternata via an EX1/2-independent 1O2 signal pathway and antagonizes JA biosynthesis.
期刊介绍:
The Journal of Experimental Botany publishes high-quality primary research and review papers in the plant sciences. These papers cover a range of disciplines from molecular and cellular physiology and biochemistry through whole plant physiology to community physiology.
Full-length primary papers should contribute to our understanding of how plants develop and function, and should provide new insights into biological processes. The journal will not publish purely descriptive papers or papers that report a well-known process in a species in which the process has not been identified previously. Articles should be concise and generally limited to 10 printed pages.