Liu Cuixia, Li Qingliang, Shen Zhengwei, Xia Ran, Chen Qian, Li Xiao, Ding Yanglin, Yang Shuhua, Serino Giovanna, Xie Qi, Yu Feifei
College of Grassland Science and Technology, China Agricultural University, Beijing, 100083, China.
State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
New Phytol. 2025 Jan;245(1):169-182. doi: 10.1111/nph.20224. Epub 2024 Nov 4.
The endoplasmic reticulum-associated degradation (ERAD) system eliminates misfolded and short-lived proteins to maintain physiological homeostasis in the cell. We have previously reported that ERAD is involved in salt tolerance in Arabidopsis. Given the central role of the phytohormone abscisic acid (ABA) in plant stress responses, we sought to identify potential intersections between the ABA and the ERAD pathways in plant stress response. By screening for the ABA response of a wide array of ERAD mutants, we isolated a gain-of-function mutant, doa10a-1, which conferred ABA hypersensitivity to seedlings. Genetic and biochemical assays showed that DOA10A is a functional E3 ubiquitin ligase which, by acting in concert with specific E2 enzymes, mediates mono-ubiquitination of the ABA receptor, followed by their relocalization to the plasma membrane. This in turn leads to enhanced ABA perception. In summary, we report here the identification of a novel RING-type E3 ligase, DOA10A, which regulates ABA perception by affecting the localization and the activity of ABA receptors through their mono-ubiquitination.
内质网相关降解（ERAD）系统可清除错误折叠和寿命短暂的蛋白质，以维持细胞内的生理稳态。我们之前报道过ERAD参与拟南芥的耐盐性。鉴于植物激素脱落酸（ABA）在植物应激反应中的核心作用，我们试图确定ABA和ERAD途径在植物应激反应中的潜在交叉点。通过筛选大量ERAD突变体的ABA反应，我们分离出一个功能获得型突变体doa10a-1，它使幼苗对ABA超敏感。遗传和生化分析表明，DOA10A是一种功能性E3泛素连接酶，它与特定的E2酶协同作用，介导ABA受体的单泛素化，随后它们重新定位到质膜。这进而导致ABA感知增强。总之，我们在此报告鉴定出一种新型的RING型E3连接酶DOA10A，它通过对ABA受体进行单泛素化来影响其定位和活性，从而调节ABA感知。
