Role of hydrogen peroxide in stress-induced programmed cell death during somatic embryogenesis in Fraxinus mandshurica

作     者：Ling Yang Cheng Wei Chao Huang Hongnan Liu Dongyan Zhang Hailong Shen Yuhua Li 

作者机构：State Key Laboratory of Tree Genetics and Breeding School of Forestry Northeast Forestry University 

出 版 物：《Journal of Forestry Research》 (林业研究（英文版）)

年 卷 期：2019年第30卷第3期

页      面：767-777页

核心收录：

学科分类：09[农学] 

基　　金：supported by the National Key R&D Program of China(2017YFD0600600) the National Natural Science Foundation of China(Nos.31400535 and 31570596) the National Basic Science Personnel Training Fund of China(No.J1210053) the Innovation Project of State Key Laboratory of Tree Genetics and Breeding(Northeast Forestry University,No.2016C01) the Fundamental Research Funds for the Central Universities(Nos.2572014CA13 and 2572018BW02) 

主　　题：Manchurian ash Somatic embryos Programmed cell death Reactive oxygen species Osmotic stress 

摘      要：We examined how reactive oxygen species, in the form of hydrogen peroxide (H2O2), affect osmotic stress–induced programmed cell death during somatic embryogenesis from cotyledon explants of Manchurian ash (Fraxinus mandshurica Rupr.). We found that substantial osmotic stress was essential for Manchurian ash somatic cells to obtain embryogenic competence. The explant cells displayed hallmarks of programmed cell death, chromatin condensation, and DNA fragmentation to oligonucleotides during somatic embryogenesis. Increasing concentrations of plant growth regulators and sucrose in the medium increased osmotic stress thereby inducing H2O2 accumulation in the explant cells. We found that H2O2 concentration was significantly decreased in explant cells when the induction medium was modified, i.e., when reducing the concentration of sucrose, which reduces the osmotic pressure of the medium, or by withdrawing plant growth regulators at mid-culture. These treatments also decreased the proportion of explant cells undergoing programmed cell death. Accordingly, a decreased rate of somatic embryo induction was observed. These results show that PCD occurred during tissue browning and death of some explant cells during somatic embryogenesis in F. mandshurica. The ROS contributed to PCD in abiotic stress stimulated F. mandshurica cells.