Ge Qiang, Zhang Yuanyuan, Xu Yunyuan, Bai Mingyi, Luo Wei, Wang Bo, Niu Yuda, Zhao Yuan, Li Shanshan, Weng Yuxiang, Wang Zhiyong, Qian Qian, Chong Kang
Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
New Phytol. 2020 Mar;225(6):2453-2467. doi: 10.1111/nph.16324. Epub 2019 Dec 28.
Coordinating stress defense and plant growth is a survival strategy for adaptation to different environments that contains a series of processes, such as, cell growth, division and differentiation. However, little is known about the coordination mechanism for protein conformation change. A cyclophilin OsCYP20-2 with a variant interacts with SLENDER RICE1 (SLR1) and OsFSD2 in the nucleus and chloroplasts, respectively, to integrate chilling tolerance and cell elongation in rice (Oryza sativa) (FSD2, Fe-superoxide dismutase 2). Mass spectrum assay showed that OsNuCYP20-2 localized at the nucleus (nuclear located OsCYP20-2) was a new variant of OsCYP20-2 that truncated 71 amino-acid residues in N-terminal. The loss-of function OsCYP20-2 mutant showed sensitivity to chilling stress with accumulation of extra reactive oxygen species (ROS). In chloroplasts, the full-length OsCYP20-2 promotes OsFSD2 forming homodimers which enhance its activity, eliminating the accumulation of ROS under chilling stress. However, the mutant had shorter epidermal cells in comparison with wild-type Hwayoung (HY). In the nucleus, OsCYP20-2 caused conformation change of SLR1 to promote its degradation for cell elongation. Our data reveal a cyclophilin with a variant with dual-localization in chloroplasts and the nucleus, which mediate chilling tolerance and cell elongation.
协调应激防御与植物生长是一种适应不同环境的生存策略，其中包含一系列过程，如细胞生长、分裂和分化。然而，关于蛋白质构象变化的协调机制却知之甚少。一种具有变体的亲环蛋白OsCYP20-2分别与水稻（Oryza sativa）细胞核和叶绿体中的SLENDER RICE1（SLR1）和OsFSD2相互作用，以整合水稻的耐冷性和细胞伸长（FSD2，铁超氧化物歧化酶2）。质谱分析表明，定位于细胞核的OsNuCYP20-2（核定位的OsCYP20-2）是OsCYP20-2的一个新变体，其N端截短了71个氨基酸残基。功能缺失的OsCYP20-2突变体对冷胁迫敏感，伴有过量活性氧（ROS）的积累。在叶绿体中，全长OsCYP20-2促进OsFSD2形成同二聚体，增强其活性，消除冷胁迫下ROS的积累。然而，与野生型华优（HY）相比，该突变体的表皮细胞较短。在细胞核中，OsCYP20-2引起SLR1的构象变化，促进其降解以实现细胞伸长。我们的数据揭示了一种具有变体的亲环蛋白，其在叶绿体和细胞核中具有双重定位，可介导耐冷性和细胞伸长。
