Wei Sijia, Bian Yangyang, Zhao Qi, Chen Sixue, Mao Jiawei, Song Chunxia, Cheng Kai, Xiao Zhen, Zhang Chuanfang, Ma Weimin, Zou Hanfa, Ye Mingliang, Dai Shaojun
Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field, Alkali Soil Natural Environmental Science Center, Ministry of Education, Northeast Forestry UniversityHarbin, China.
Key Laboratory of Separation Sciences for Analytical Chemistry, National Chromatographic R&A Center, Dalian Institute of Chemical Physics, Chinese Academy of SciencesDalian, China.
Front Plant Sci. 2017 May 23;8:810. doi: 10.3389/fpls.2017.00810. eCollection 2017.
Palmella stage is critical for some unicellular algae to survive in extreme environments. The halotolerant algae is a good single-cell model for studying plant adaptation to high salinity. To investigate the molecular adaptation mechanism in salinity shock-induced palmella formation, we performed a comprehensive physiological, proteomics and phosphoproteomics study upon palmella formation of using dimethyl labeling and Ti-immobilized metal ion affinity chromatography (IMAC) proteomic approaches. We found that 151 salinity-responsive proteins and 35 salinity-responsive phosphoproteins were involved in multiple signaling and metabolic pathways upon palmella formation. Taken together with photosynthetic parameters and enzyme activity analyses, the patterns of protein accumulation and phosphorylation level exhibited the mechanisms upon palmella formation, including dynamics of cytoskeleton and cell membrane curvature, accumulation and transport of exopolysaccharides, photosynthesis and energy supplying (i.e., photosystem II stability and activity, cyclic electron transport, and C4 pathway), nuclear/chloroplastic gene expression regulation and protein processing, reactive oxygen species homeostasis, and salt signaling transduction. The salinity-responsive protein-protein interaction (PPI) networks implied that signaling and protein synthesis and fate are crucial for modulation of these processes. Importantly, the 3D structure of phosphoprotein clearly indicated that the phosphorylation sites of eight proteins were localized in the region of function domain.
胶群体阶段对于一些单细胞藻类在极端环境中生存至关重要。耐盐藻类是研究植物适应高盐度的良好单细胞模型。为了研究盐胁迫诱导胶群体形成的分子适应机制，我们使用二甲基标记和钛固定金属离子亲和色谱（IMAC）蛋白质组学方法，对胶群体形成进行了全面的生理、蛋白质组学和磷酸化蛋白质组学研究。我们发现，151种盐响应蛋白和35种盐响应磷酸化蛋白参与了胶群体形成过程中的多种信号传导和代谢途径。结合光合参数和酶活性分析，蛋白质积累和磷酸化水平模式展示了胶群体形成的机制，包括细胞骨架和细胞膜曲率的动态变化、胞外多糖的积累和运输、光合作用和能量供应（即光系统II的稳定性和活性、循环电子传递和C4途径）、核/叶绿体基因表达调控和蛋白质加工、活性氧稳态以及盐信号转导。盐响应蛋白质-蛋白质相互作用（PPI）网络表明，信号传导以及蛋白质合成和命运对于调节这些过程至关重要。重要的是，磷酸化蛋白的三维结构清楚地表明，8种蛋白质的磷酸化位点位于功能域区域。
