State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China.
State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
J Genet Genomics. 2022 Aug;49(8):766-775. doi: 10.1016/j.jgg.2022.06.009. Epub 2022 Jul 5.
Salt stress adversely affects plant growth, development, and crop yield. Rice (Oryza sativa L.) is one of the most salt-sensitive cereal crops, especially at the early seedling stage. Mitogen-activated protein kinase (MAPK/MPK) cascades have been shown to play critical roles in salt response in Arabidopsis. However, the roles of the MPK cascade signaling in rice salt response and substrates of OsMPK remain largely unknown. Here, we report that the salt-induced OsMPK4-Ideal Plant Architecture 1 (IPA1) signaling pathway regulates the salt tolerance in rice. Under salt stress, OsMPK4 could interact with IPA1 and phosphorylate IPA1 at Thr180, leading to degradation of IPA1. Genetic evidence shows that IPA1 is a negative regulator of salt tolerance in rice, whereas OsMPK4 promotes salt response in an IPA1-dependent manner. Taken together, our results uncover an OsMPK4-IPA1 signal cascade that modulates the salt stress response in rice and sheds new light on the breeding of salt-tolerant rice varieties.
盐胁迫会对植物的生长、发育和作物产量产生不利影响。水稻（Oryza sativa L.）是最敏感的谷类作物之一，尤其是在早期幼苗阶段。有研究表明，丝裂原活化蛋白激酶（MAPK/MPK）级联反应在拟南芥的盐响应中起着关键作用。然而，MPK 级联信号在水稻盐响应中的作用和 OsMPK 的底物仍知之甚少。在这里，我们报告说，盐诱导的 OsMPK4-理想植物形态 1（IPA1）信号通路调节水稻的耐盐性。在盐胁迫下，OsMPK4 可以与 IPA1 相互作用，并在 Thr180 处磷酸化 IPA1，导致 IPA1 的降解。遗传证据表明，IPA1 是水稻耐盐性的负调控因子，而 OsMPK4 以 IPA1 依赖的方式促进盐响应。综上所述，我们的研究结果揭示了一个 OsMPK4-IPA1 信号级联，调节水稻的盐胁迫反应，为耐盐水稻品种的培育提供了新的思路。
