Li Jijun, Iqbal Sidra, Zhang Yuting, Chen Yahui, Tan Zengdong, Ali Usman, Guo Liang
National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China.
Department of Agriculture, University of Swabi, Swabi 23430, Pakistan.
Plants (Basel). 2021 Apr 3;10(4):693. doi: 10.3390/plants10040693.
Flooding results in significant crop yield losses due to exposure of plants to hypoxic stress. Various studies have reported the effect of flooding stress at seedling establishment or later stages. However, the molecular mechanism prevailing at the germination stage under flooding stress remains enigmatic. The present study highlights the comparative transcriptome analysis in two rapeseed lines, i.e., flooding-tolerant (Santana) and -sensitive (23651) lines under control and 6-h flooding treatments at the germination stage. A total of 1840 up-regulated and 1301 down-regulated genes were shared by both lines in response to flooding. There were 4410 differentially expressed genes (DEGs) with increased expression and 4271 DEGs with reduced expression shared in both control and flooding conditions. Gene ontology (GO) enrichment analysis revealed that "transcription regulation", "structural constituent of cell wall", "reactive oxygen species metabolic", "peroxidase", oxidoreductase", and "antioxidant activity" were the common processes in rapeseed flooding response. In addition, the processes such as "hormone-mediated signaling pathway", "response to organic substance response", "motor activity", and "microtubule-based process" are likely to confer rapeseed flooding resistance. Mclust analysis clustered DEGs into nine modules; genes in each module shared similar expression patterns and many of these genes overlapped with the top 20 DEGs in some groups. This work provides a comprehensive insight into gene responses and the regulatory network in rapeseed flooding stress and provides guidelines for probing the underlying molecular mechanisms in flooding resistance.
洪水会导致植物遭受缺氧胁迫，从而造成显著的作物产量损失。各种研究报告了洪水胁迫在幼苗期或后期的影响。然而，洪水胁迫下种子萌发阶段的分子机制仍然不明。本研究重点对两个油菜品种进行了比较转录组分析，即耐淹品种（桑塔纳）和敏感品种（23651），在萌发阶段分别进行对照和6小时淹水处理。两个品种在淹水胁迫下共有1840个上调基因和1301个下调基因。在对照和淹水条件下共有4410个差异表达基因（DEG）表达增加，4271个DEG表达减少。基因本体（GO）富集分析表明，“转录调控”、“细胞壁结构成分”、“活性氧代谢”、“过氧化物酶”、“氧化还原酶”和“抗氧化活性”是油菜对淹水响应的常见过程。此外，“激素介导的信号通路”、“对有机物质的响应”、“运动活性”和“基于微管的过程”等过程可能赋予油菜耐淹性。Mclust分析将DEG聚类为九个模块；每个模块中的基因具有相似的表达模式，其中许多基因与某些组中的前20个DEG重叠。这项工作全面深入地了解了油菜在淹水胁迫下的基因响应和调控网络，并为探究耐淹性的潜在分子机制提供了指导。
