Plastoglobules compartmentalize nitrogen assimilation in maize

• 成果类型: Article
• 署名作者: Chen, Di; Gao, Lulu; Li, Shujun; Cheng, Yiqiu; Wu, Xiaoxian; Li, Wenhao; Zhang, Jinman; Fu, Xueling; Xiang, Pan; Sun, Lu; Chen, Zhiteng; Zhang, Hua; Li, Youliang; Luo, Shiqi; You, Chong; Sun, Linhan; Huang, Xing; Zhu, Yidong; Zeng, Xing; Wang, Wenqin; He, Yan; Wang, Haihai; Zhang, Yu; Chen, Xuewei; Wu, Yongrui; Huang, Yongcai
• 署名单位: Sichuan Agricultural University; Chinese Academy of Sciences; Center for Excellence in Molecular Plant Sciences, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Northeast Agricultural University - China; Shanghai Normal University; Chinese Academy of Sciences; Institute of Genetics & Developmental Biology, CAS
• 刊物名称: NATURE
• ISSN/ISSBN: 0028-0836; 1476-4687
• DOI: 10.1038/s41586-026-10610-8
• 发表日期: 2026-07-16
• 关键词: OSMIOPHILIC GLOBULES; GLUTAMINE-SYNTHETASE; molecular-genetics; localization; chloroplasts; protein; photosynthesis; accumulation; mitochondria; integration

摘要

Efficient nitrogen assimilation is important for sustainable agriculture1, yet its subcellular organization remains unknown. Here we show that plastoglobules (PGs) in the chloroplasts of mesophyll cells function as a metabolic hub that orchestrates nitrogen utilization in maize. Nitrogen-responsive dynamics of PGs represent a conserved feature across plant species. We identify two key enzymes, nitrite reductase 2 (ZmNIR2) and glutamine synthetase 1 (ZmGLN1), specifically targeted to PGs by a chloroplast transit peptide and hydrophobic region. Cryogenic electron microscopy analysis of recombinant ZmGLN1 shows a decameric complex, enabling a metabolon with ZmNIR2 for enhanced efficiency. Among two NIR and six GLN enzymes, ZmNIR2 and ZmGLN1 are the primary PG-localized components that orchestrate sub-organellar nitrogen assimilation and dictate nitrogen use efficiency. Genetic variation in ZmNIR2 splicing in cultivated germplasm generates a PG-targeted isoform (ZmNIR2T1) that boosts NUE. Our work establishes PGs as a central compartment for primary nitrogen assimilation, providing a promising strategy to develop high-NUE crops for global food security.