PBS3 Protects EDS1 from Proteasome-Mediated Degradation in Plant Immunity
PBS3 Protects EDS1 from Proteasome-Mediated Degradation in Plant Immunity
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PBS3 保护 EDS1 免受植物免疫中蛋白酶体介导的降解
DOI：
10.1016/j.molp.2019.01.023
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发表时间：
2019-05-06
期刊：
影响因子：
27.5
通讯作者：
Fu, Zheng Qing
中科院分区：
文献类型：
--
作者：
Chang, Ming;Zhao, Jinping;Fu, Zheng Qing
植物免疫受正调节因子如PBS 3和EDS 1以及负调节因子如NPR 3和NPR 4控制。然而，这些重要的免疫调节因子之间的关系仍然难以捉摸。在这项研究中，我们发现PBS3在细胞质和细胞核中与EDS1相互作用，并且是EDS1蛋白积累所必需的。NPR3和NPR4作为水杨酸受体和基于Cullin 3的E3连接酶的衔接子，通过26S蛋白酶体与EDS 1相互作用并介导其降解。我们进一步发现，PBS 3通过减少EDS 1与Cullin 3衔接子NPR 3和NPR 4的结合来抑制EDS 1的多聚泛素化和随后的降解。此外，我们发现，PBS3和EDS1除了效应子触发的免疫外，还有助于PAMP触发的免疫。总的来说，我们的研究揭示了一种新的机制，植物通过抑制植物免疫中的积极参与者的降解来微调防御反应。
Plant immunity is controlled by both positive regulators such as PBS3 and EDS1 and negative regulators such as NPR3 and NPR4. However, the relationships among these important immune regulators remain elusive. In this study, we found that PBS3 interacts with EDS1 in both the cytoplasm and the nucleus, and is required for EDS1 protein accumulation. NPR3 and NPR4, which function as salicylic acid receptors and adaptors of Cullin3-based E3 ligase, interact with and mediate the degradation of EDS1 via the 26S proteasome. We further discovered that PBS3 inhibits the polyubiquitination and subsequent degradation of EDS1 by reducing the association of EDS1 with the Cullin3 adaptors NPR3 and NPR4. Furthermore, we showed that PBS3 and EDS1 also contribute to PAMP-triggered immunity in addition to effector-triggered immunity. Collectively, our study reveals a novel mechanism by which plants fine-tune defense responses by inhibiting the degradation of a positive player in plant immunity.