Ge Linhao, Jia Mingxuan, Shan Hongying, Gao Weifang, Jiang Lu, Cui Hongguang, Cheng Xiaofei, Uzest Marilyne, Zhou Xueping, Wang Aiming, Li Fangfang
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education and College of Plant Protection, Hainan University, Haikou, Hainan, China.
Nat Commun. 2025 Jan 2;16(1):157. doi: 10.1038/s41467-024-55288-6.
Potyvirids are the largest group of plant RNA viruses. Pelota, a core component of RNA quality controls (RQC), promotes the degradation of potyvirids' genomic RNA by recognizing a specific GA motif. Here we demonstrate that the viral RNA-dependent RNA polymerase, NIb, acts as a SUMOylation decoy to effectively reduce Pelota SUMOylation by competing with SCE1 to inhibit Pelota-mediated RQC. TuMV NIb is comprised of two functional SUMO interacting motif (SIM): SIM2 and SIM3. The former is identified as the key site for NIb's SUMOylation by SUMO3, whereas the latter is responsible for the interaction with SCE1. These two SIMs are conserved among the majority of potyvirids-encoded NIbs. Thus, virus protein-mediated SUMOylation decoy strategy to suppress host defense may be a common feature in plant virus pathosystems. These findings highlight a dynamic interplay between plant defense mechanism and viral counter-strategy by orchestrating the post-translational modifications of virus and host defense components.
马铃薯Y病毒科是最大的植物RNA病毒组。Pelota是RNA质量控制（RQC）的核心组成部分，通过识别特定的GA基序促进马铃薯Y病毒科基因组RNA的降解。在这里，我们证明病毒RNA依赖性RNA聚合酶NIb作为一种类泛素化诱饵，通过与SCE1竞争抑制Pelota介导的RQC，有效降低Pelota的类泛素化。芜菁花叶病毒NIb由两个功能性类泛素相互作用基序（SIM）组成：SIM2和SIM3。前者被确定为SUMO3对NIb进行类泛素化的关键位点，而后者负责与SCE1相互作用。这两个SIM在大多数马铃薯Y病毒科编码的NIb中是保守的。因此，病毒蛋白介导的抑制宿主防御的类泛素化诱饵策略可能是植物病毒致病系统中的一个共同特征。这些发现通过协调病毒和宿主防御成分的翻译后修饰，突出了植物防御机制与病毒应对策略之间的动态相互作用。
