Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800, Rd. Dong Chuan, Shanghai, PR China.
Plant Sci. 2013 Nov;212:37-47. doi: 10.1016/j.plantsci.2013.07.011. Epub 2013 Jul 29.
Cryopreservation can be a safe and cost-effective tool for the long-term storage of plant germplasm. In Arabidopsis, the ability to recover from cryogenic treatment was lost as growth progressed. Growth could be restored in 48-h seedlings, whereas 72-h seedlings died after cryogenic treatment. Why seedling age and survival are negatively correlated is an interesting issue. A comparative transcriptomics was performed to screen differentially expressed genes between 48- and 72-h seedlings after exposure to cryoprotectant. Among differentially expressed genes, oxidative stress response genes played important roles in cryoprotectant treatment, and peroxidation was a key factor related to cell survival. Seedlings underwent more peroxidation at 72-h than at 48-h. A comprehensive analysis indicated that peroxidation injured membrane systems leading to photophosphorylation and oxidative phosphorylation damage. Furthermore, the apoptosis-like events were found in cryogenic treatment of Arabidopsis seedlings. 48- and 72-h seedlings underwent different degrees of membrane lipid peroxidation during cryoprotectant treatment, and reducing the injury of oxidative stress was an important factor to successful cryopreservation. This study provided a novel insight of genetic regulatory mechanisms in cryopreservation, and established an excellent model to test and evaluate the effect of exogenous antioxidants and conventional cryoprotectants in plant cryopreservation.
低温保存可以作为植物种质长期储存的一种安全且具有成本效益的工具。在拟南芥中，随着生长的进行，其从低温处理中恢复的能力丧失。在 48 小时的幼苗中可以恢复生长，而在经过低温处理后 72 小时的幼苗则死亡。为什么幼苗年龄和存活率呈负相关是一个有趣的问题。进行了比较转录组学研究，以筛选暴露于保护剂后 48 小时和 72 小时幼苗之间差异表达的基因。在差异表达的基因中，氧化应激反应基因在保护剂处理中发挥重要作用，而过氧化作用是与细胞存活相关的关键因素。72 小时的幼苗比 48 小时的幼苗经历了更多的过氧化作用。综合分析表明，过氧化作用损伤了膜系统，导致光磷酸化和氧化磷酸化损伤。此外，在拟南芥幼苗的低温处理中发现了类似细胞凋亡的事件。在保护剂处理过程中，48 小时和 72 小时的幼苗都经历了不同程度的膜脂过氧化，减少氧化应激的损伤是成功低温保存的一个重要因素。本研究为低温保存的遗传调控机制提供了新的见解，并建立了一个优秀的模型，用于测试和评估外源抗氧化剂和常规保护剂在植物低温保存中的效果。
