Wang Juan, Nguyen Nam Khoa, Liu Dongping, Jwa Nam-Soo
Division of Integrative Bioscience and Biotechnology, College of Life Sciences, Sejong University, Seoul 05006, Republic of Korea.
Antioxidants (Basel). 2024 Aug 20;13(8):1013. doi: 10.3390/antiox13081013.
Mitogen-activated protein (MAP) kinase (MAPK) signaling pathway is important in plant immune responses, involved in iron- and reactive oxygen species (ROS)-dependent ferroptotic cell death mediated by Ca. High Ca influx triggered iron-dependent ROS accumulation, lipid peroxidation, and subsequent hypersensitive response (HR) cell death in rice (). Apoplastic Ca chelation by EGTA during avirulent infection altered Ca, ROS, and Fe accumulation, increasing rice susceptibility to infection. By contrast, acibenzolar--methyl (ASM), a plant defense activator, significantly enhanced Ca influx, and HO accumulation, triggering rice ferroptotic cell death during virulent infection. Here, we report a novel role of the MAPK signaling pathway in regulating cytoplasmic Ca increase during ferroptotic cell death in rice immunity, using the knockout mutant rice. The knockout of rice impaired the ROS accumulation, lipid peroxidation, and iron accumulation during avirulent infection. This study has shown that OsMEK2 could positively regulate iron- and ROS-dependent ferroptotic cell death in rice by modulating the expression of , , , and . This modulation indicates a possible mechanism for how OsMEK2 participates in Ca regulation in rice ferroptotic cell death, suggesting its broader role in plant immune responses in response to infection.
丝裂原活化蛋白（MAP）激酶（MAPK）信号通路在植物免疫反应中很重要，参与由钙介导的铁和活性氧（ROS）依赖性铁死亡细胞死亡。高钙内流引发了水稻中铁依赖性ROS积累、脂质过氧化以及随后的过敏反应（HR）细胞死亡（）。在无毒感染期间，EGTA对质外体钙的螯合改变了钙、ROS和铁的积累，增加了水稻对感染的易感性。相比之下，植物防御激活剂烯丙苯噻唑（ASM）显著增强了钙内流和过氧化氢积累，在毒性感染期间引发水稻铁死亡细胞死亡。在这里，我们利用敲除突变体水稻报道了MAPK信号通路在调节水稻免疫中铁死亡细胞死亡期间细胞质钙增加方面的新作用。水稻的敲除削弱了无毒感染期间的ROS积累、脂质过氧化和铁积累。这项研究表明，OsMEK2可以通过调节、、和的表达来正向调节水稻中铁和ROS依赖性铁死亡细胞死亡。这种调节表明了OsMEK2参与水稻铁死亡细胞死亡中钙调节的一种可能机制，暗示了其在响应感染的植物免疫反应中的更广泛作用。
