College of Animal Science and Technology, Southwest University, Chongqing, 400716, China; College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China.
College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China.
Plant Physiol Biochem. 2021 Jun;163:285-295. doi: 10.1016/j.plaphy.2021.04.007. Epub 2021 Apr 20.
Cuticular wax and cutin are directly involved in the mechanisms by which plants acclimate to water-limited environments. However, how the two lipid forms balance their contributions to plant drought-tolerance is still not clear. The present study examined the responses of cutin monomers and cuticular waxes to drought stress in two sorghum (Sorghum bicolor (L.) Moench) cultivars, drought-tolerant cv. Kangsi and drought-sensitive cv. Hongyingzi, by combining lipidomic and transcriptomic analysis. Drought increased total cutin contents by 41.3%, the contents of alkanoic acids by 72.6% and 2-hydroxyacids by 117.8% in Kangsi but unchanged those in Hongyingzi. The abundance of cutin monomers were relatively stable for cv Hongyingzi, excepting for a decrease of ω-hydroxyacids from 35.0% to 27.4% in drought-stressed plants. However, for cv Kangsi, the abundance of ω-hydroxyacids decreased from 36.8% to 21.0% and that of alkanoic acids increased from 30.5% to 37.1% in drought-stressed plants. Drought increased total wax coverage in Hongyingzi but reduced it in Kangsi. However, the abundance of aldehydes decreased from 51.2% to 39.3% in drought-stressed cv Kangsi, but increased from 25.2% to 36.1% in drought-stressed cv Hongyingzi. A decrease of sterols (by 76%) and an increase of primary alcohol (by 443%) was also observed in drought-stressed cv Hongyingzi. Transcriptome analysis also revealed that many genes implicated by homology in cutin monomer and cuticular wax biosynthesis also differed in their responses to drought stress between the two sorghum cultivars. Therefore, sorghum cultivars differed in their mechanisms in adjusting chemical profiles of both cutin and cuticular wax under water deficit condition.
角质层蜡质和角质是植物适应水分受限环境的机制中直接涉及的物质。然而，这两种脂质形式如何平衡它们对植物耐旱性的贡献仍然不清楚。本研究通过联合脂质组学和转录组学分析，研究了两种高粱（高粱（Sorghum bicolor (L.) Moench）品种，耐旱品种康西和耐旱敏感品种红鹰子，角质单体和角质层蜡质对干旱胁迫的响应。干旱使康西的总角质含量增加了 41.3%，烷酸含量增加了 72.6%，2-羟基酸含量增加了 117.8%，而红鹰子的角质含量则没有变化。对于红鹰子品种，角质单体的丰度相对稳定，除了干旱胁迫下的 ω-羟基酸从 35.0%下降到 27.4%。然而，对于康西品种，干旱胁迫下 ω-羟基酸的丰度从 36.8%下降到 21.0%，烷酸的丰度从 30.5%增加到 37.1%。干旱增加了红鹰子的总蜡质覆盖度，但降低了康西的总蜡质覆盖度。然而，干旱胁迫下康西品种的醛含量从 51.2%下降到 39.3%，而干旱胁迫下红鹰子品种的醛含量从 25.2%增加到 36.1%。干旱胁迫下，红鹰子品种的固醇（下降 76%）和一级醇（增加 443%）也有所增加。转录组分析还表明，在角质单体和角质层蜡质生物合成中具有同源性的许多基因，在两个高粱品种对干旱胁迫的响应中也存在差异。因此，高粱品种在水分亏缺条件下，角质和角质层蜡质化学特征的调节机制存在差异。
