Wang Qi, Huang Siyu, Huang Qingqing, Yu Yao, Li Huafen, Wan Yanan
Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
Innovation Team of Heavy Metal Ecotoxicity and Pollution Remediation, Ministry of Agriculture and Rural Affairs (MARA), Agro-Environmental Protection Institute, MARA, Tianjin 300191, China.
Plants (Basel). 2024 Jan 27;13(3):380. doi: 10.3390/plants13030380.
An in-depth understanding of Se uptake and metabolism in plants is necessary for developing Se biofortification strategies. Thus, hydroponic experiments were conducted to investigate the associated processes and mechanisms of organic Se (selenomethionine (SeMet) and selenomethionine-oxide (SeOMet)) uptake, translocation, transformation and their interaction in wheat, in comparison to inorganic Se. The results showed that Se uptake by the roots and the root-to-shoot translocation factor under the SeMet treatment were higher than those under the selenite, selenate and SeOMet treatments. The uptake and translocation of SeMet were higher than those of SeOMet within 72 h, although the differences gradually narrowed with time. The uptake of SeMet and SeOMet was also sensitive to the aquaporin inhibitor: AgNO addition resulted in 99.5% and 99.9% inhibitions of Se in the root in the SeMet and SeOMet treatments, respectively. Once absorbed by the root, they rapidly assimilated to other Se forms, and SeMet and Se-methyl-selenocysteine (MeSeCys) were the dominant species in SeMet- and SeOMet-treated plants, while notably, an unidentified Se form was also found in the root and xylem sap under the SeMet treatment. In addition, within 16 h, SeOMet inhibited the uptake and translocation of SeMet, while the inhibition was weakened with longer treatment time. Taken together, the present study provides new insights for the uptake and transformation processes of organic Se within plants.
深入了解植物中硒的吸收和代谢对于制定硒生物强化策略至关重要。因此，进行了水培实验，以研究与无机硒相比，小麦中有机硒（硒代蛋氨酸（SeMet）和硒代蛋氨酸亚砜（SeOMet））的吸收、转运、转化及其相互作用的相关过程和机制。结果表明，SeMet处理下根系对硒的吸收以及根向地上部的转运系数高于亚硒酸盐、硒酸盐和SeOMet处理。在72小时内，SeMet的吸收和转运高于SeOMet，尽管差异随时间逐渐缩小。SeMet和SeOMet的吸收对水通道蛋白抑制剂也很敏感：添加AgNO分别导致SeMet和SeOMet处理的根系中硒的吸收抑制率达到99.5%和99.9%。一旦被根系吸收，它们会迅速同化为其他硒形态，在SeMet和SeOMet处理的植物中，SeMet和硒甲基硒代半胱氨酸（MeSeCys）是主要形态，值得注意的是，在SeMet处理下，在根和木质部汁液中还发现了一种未鉴定的硒形态。此外，在16小时内，SeOMet抑制了SeMet的吸收和转运，而随着处理时间延长，这种抑制作用减弱。综上所述，本研究为植物体内有机硒的吸收和转化过程提供了新的见解。
