Marriboina Sureshbabu, Sekhar Kalva Madhana, Subramanyam Rajagopal, Reddy Attipalli Ramachandra
Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, India.
Front Plant Sci. 2022 Jan 24;12:771992. doi: 10.3389/fpls.2021.771992. eCollection 2021.
Cultivation of potential biofuel tree species such as would rehabilitate saline marginal lands toward economic gains. We carried out a physiological, biochemical, and proteomic analysis to identify key regulatory responses which are associated with salt tolerance mechanisms at the shoot and root levels. seedlings were grown at 300 and 500 mM NaCl (∼3% NaCl; sea saline equivalent) concentrations for 15 and 30 days, gas exchange measurements including leaf net photosynthetic rate ( ), stomatal conductance ( ), and transpiration rate (), and varying chlorophyll fluorescence kinetics were recorded. The whole root proteome was quantified using the free-labeled nanoLC-MS/MS technique to investigate crucial proteins involved in signaling pathways associated with salt tolerance. showed no visible salt-induced morphological symptoms. However, showed about 50% decline in gas exchange parameters including , , and 15 and 30 days after salt treatment (DAS). The maximum potential quantum efficiency of photosystem (PS) II (Fv/Fm) was maintained at approximately 0.8 in salt-treated plants. The thermal component of PSII (DIo) was increased by 1.6-fold in the salt-treated plants. A total of 1,062 protein species were identified with 130 commonly abundant protein species. Our results also elucidate high abundance of protein species related to flavonoid biosynthesis, seed storage protein species, and carbohydrate metabolism under salt stress. Overall, these analyses suggest that exhibited sustained leaf morphology by lowering net photosynthetic rates and emitting most of its light energy as heat. Our root proteomic results indicated that these protein species were most likely recruited from secondary and anaerobic metabolism, which could provide defense for roots against Na toxicity under salt stress conditions.
种植诸如 等潜在的生物燃料树种，将使盐碱边际土地恢复生机并带来经济收益。我们进行了生理、生化和蛋白质组学分析，以确定与地上部和根部耐盐机制相关的关键调控反应。 幼苗在300和500 mM NaCl（约3% NaCl；相当于海盐水浓度）浓度下培养15天和30天，记录了包括叶片净光合速率（ ）、气孔导度（ ）和蒸腾速率（ ）在内的气体交换测量值以及不同的叶绿素荧光动力学。使用无标记的纳升液相色谱 - 串联质谱技术对整个根系蛋白质组进行定量，以研究参与耐盐相关信号通路的关键蛋白质。 未表现出明显的盐诱导形态症状。然而，在盐处理15天和30天后（DAS）， 的气体交换参数包括 、 和 下降了约50%。盐处理植株中光系统（PS）II的最大潜在量子效率（Fv/Fm）维持在约0.8。盐处理植株中PSII的热组分（DIo）增加了1.6倍。共鉴定出1062种蛋白质，其中有130种是常见的丰富蛋白质。我们的结果还阐明了盐胁迫下与类黄酮生物合成、种子贮藏蛋白和碳水化合物代谢相关的高丰度蛋白质。总体而言，这些分析表明， 通过降低净光合速率并将大部分光能以热的形式散发，从而维持叶片形态。我们的根系蛋白质组学结果表明，这些蛋白质很可能来自次生代谢和厌氧代谢，这可以在盐胁迫条件下为根系抵御Na毒性提供保护。
