Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China.
Plant Cell Rep. 2015 Feb;34(2):331-43. doi: 10.1007/s00299-014-1712-6. Epub 2014 Dec 5.
Silicon induces cell death when ethylene is suppressed in cultured tobacco BY-2 cells. There is a crosstalk between Si and ethylene signaling. Silicon (Si) is beneficial for plant growth. It alleviates both biotic and abiotic stresses in plants. How Si works in plants is still mysterious. This study investigates the mechanism of Si-induced cell death in tobacco BY-2 cell cultures when ethylene is suppressed. Results showed that K2SiO3 alleviated the damage of NaCl stress. Si treatment rapidly increased ethylene emission and the expression of ethylene biosynthesis genes. Treatments with Si + Ag and Si + aminooxyacetic acid (AOA, ethylene biosynthesis inhibitor) reduced the cell growth and increased cell damage. The treatment with Si + Ag induced hydrogen peroxide (H2O2) generation and ultimately cell death. Some nucleus of BY-2 cells treated with Si + Ag appeared TUNEL positive. The inhibition of H2O2 and nitric oxide (NO) production reduced the cell death rate induced by Si + Ag treatment. Si eliminated the up-regulation of alternative pathway by Ag. These data suggest that ethylene plays an important role in Si function in plants. Without ethylene, Si not only failed to enhance plant resistance, but also elevated H2O2 generation and further induced cell death in tobacco BY-2 cells.
当乙烯在培养的烟草 BY-2 细胞中被抑制时，硅会诱导细胞死亡。硅和乙烯信号之间存在串扰。硅（Si）对植物生长有益。它可以减轻植物的生物和非生物胁迫。硅在植物中的作用仍然是神秘的。本研究调查了当乙烯被抑制时，硅诱导烟草 BY-2 细胞培养物中细胞死亡的机制。结果表明，K2SiO3 缓解了 NaCl 胁迫的损伤。硅处理迅速增加了乙烯的排放和乙烯生物合成基因的表达。用 Si + Ag 和 Si + 氨基氧乙酸（AOA，乙烯生物合成抑制剂）处理会降低细胞生长并增加细胞损伤。用 Si + Ag 处理会诱导过氧化氢（H2O2）的产生，最终导致细胞死亡。一些用 Si + Ag 处理的 BY-2 细胞核出现 TUNEL 阳性。抑制 H2O2 和一氧化氮（NO）的产生会降低 Si + Ag 处理诱导的细胞死亡率。硅消除了 Ag 对替代途径的上调。这些数据表明，乙烯在植物的硅功能中起着重要作用。没有乙烯，硅不仅未能增强植物的抗性，反而增加了 H2O2 的产生，并进一步诱导烟草 BY-2 细胞死亡。
