Cui Can, Wang Zhen, Su Yingjuan, Wang Ting
School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
Research Institute of Sun Yat-sen University in Shenzhen, Shenzhen, China.
Front Plant Sci. 2022 Apr 8;13:856527. doi: 10.3389/fpls.2022.856527. eCollection 2022.
As a primary goal, adaptation to cold climate could expand an invasion range of exotic plants. Here, we aimed to explore the regulation strategy of seed development under cold stress through molecular physiology and multi-omics analysis. Significant increase of hydrogen peroxide, malondialdehyde, and electrolyte leakage observed under cold stress revealed that oxidative damage within seed cells was induced in the initial germination phase. Proteomic data underscored an activation of antioxidant activity to maintain redox homeostasis, with a cluster of antioxidant proteins identified. Genomic-wide transcriptome, in combination with time-series whole-genome bisulfite sequencing mining, elucidated that seven candidate genes, which were the target of DNA demethylation-dependent ROS scavenging, were possibly associated with an germ break. Progressive gain of CHH context DNA methylation identified in an early germination phrase suggested a role of a DNA methylation pathway, while an active DNA demethylation pathway was also initiated during late seed development, which was in line with the expression trend of methylation and demethylation-related genes verified through qRT-PCR. These data pointed out that cold-dependent DNA demethylation and an antioxidant regulatory were involved together in restoring seed germination. The expression level of total 441 genes presented an opposite trend to the methylation divergence, while the expression of total 395 genes was proved to be negatively associated with their methylation levels. These data provided new insights into molecular reprograming events during seed development.
作为一个主要目标，适应寒冷气候可能会扩大外来植物的入侵范围。在这里，我们旨在通过分子生理学和多组学分析来探索冷胁迫下种子发育的调控策略。冷胁迫下观察到的过氧化氢、丙二醛和电解质渗漏显著增加，表明在种子细胞的初始萌发阶段诱导了氧化损伤。蛋白质组学数据强调了抗氧化活性的激活以维持氧化还原稳态，并鉴定出一组抗氧化蛋白。全基因组转录组与时间序列全基因组亚硫酸氢盐测序挖掘相结合，阐明了七个候选基因，它们是DNA去甲基化依赖性活性氧清除的靶点，可能与种子萌发有关。在早期萌发阶段鉴定出的CHH上下文DNA甲基化的逐步增加表明了DNA甲基化途径的作用，而在种子发育后期也启动了活跃的DNA去甲基化途径，这与通过qRT-PCR验证的甲基化和去甲基化相关基因的表达趋势一致。这些数据指出，冷依赖性DNA去甲基化和抗氧化调节共同参与恢复种子萌发。总共441个基因的表达水平呈现出与甲基化差异相反的趋势，而总共395个基因的表达被证明与其甲基化水平呈负相关。这些数据为种子发育过程中的分子重编程事件提供了新的见解。
