论文题目：Functional Dissection of a Wheat NLR Protein Reveals a Minimal Active Region and Key Regulatory Sites for Immune Signalling
论文作者：Xiaoxu Zhu, Shuo Jiang, Jinchen Zhao, Fangfang Peng, Ran Zhao, Xinnuo Li, Yi Luo, Zhihao Xiong, Qi Li, Filip Rolland, Zhensheng Kang, Xiaojie Wang, Yunqi Liu, Li Huang, Xiaojing Wang
论文摘要：Nucleotide-binding site (NBS) leucine-rich repeat (LRR) receptors (NLRs) are crucial for plant immunity but often come with trade-offs in plant growth. Understanding the mechanisms of their self-regulating activity for controlled immune responses is essential for optimising crop resistance. In this study, we investigated the activity fine-tuning of the wheat NLR protein NLRMoro, derived from the cultivars Moro and AvS + Yr10. Overexpression in Nicotiana benthamiana and wheat demonstrated that NLRMoro, or its N-terminal coiled-coil (CC) domain alone, auto-activated cell death and that plasma membrane-localised NLRMoro-CC conferred stripe rust resistance through induction of hypersensitive response, reactive oxygen species accumulation and Ca2+ influx. Through truncation analysis, we identified the amino acids 62–116 region within the CC domain as the minimal active region, essential and sufficient for its activity. Further investigation revealed that the adjacent central NBS domain suppresses the signalling activity of CC, while the C-terminal LRR domain alleviates this suppression, both exclusively via intramolecular interactions. Critical sites outside the CC domain, including the P-loop, RNBS-A and MHD motifs and the phosphorylation site S198, were found to significantly influence NLRMoro-induced cell death, presenting potential targets for fine-tuning NLR activity. This study advances our understanding of CC-NLR protein regulation and provides a theoretical foundation for optimising NLR activity to balance growth–defence trade-offs in plants.
核苷酸结合位点（NBS）-富含亮氨酸重复序列（LRR）受体（NLRs）在植物免疫中起着关键作用，但往往伴随对植物生长的权衡效应。因此，解析其自我调控机制以实现可控的免疫反应，对优化作物抗病性具有重要意义。本研究聚焦于小麦NLR蛋白NLRMoro（来源于品种Moro及AvS + Yr10）的活性精细调控机制。通过在烟草和小麦中过表达发现，NLRMoro及其仅含N端卷曲螺旋（CC）结构域的片段均可自主激活细胞死亡；定位于质膜的NLRMoro-CC可通过诱导过敏反应、活性氧（ROS）积累及Ca²⁺内流，赋予植株对条锈病的抗性。通过截短分析，我们确定CC结构域内的第62–116位氨基酸区域为其最小功能区域，既是其活性所必需，也足以独立发挥功能。进一步研究表明，中央的NBS结构域可抑制CC的信号传导活性，而C端的LRR结构域则缓解这种抑制作用，两者均通过分子内相互作用实现这一调控。此外，CC结构域以外的多个关键位点，包括P-loop、RNBS-A、MHD基序以及磷酸化位点S198均显著影响NLRMoro诱导的细胞死亡，为精准调控NLR活性提供了潜在干预靶点。本研究深化了对CC-NLR蛋白调控机制的理解，为通过优化NLR活性以平衡植物生长与防御之间的权衡关系提供了理论基础.
论文链接：https://pmc.ncbi.nlm.nih.gov/articles/PMC12971249/