College of Horticulture, Key Laboratory of Landscape Agriculture, Ministry of Agriculture and Rural Affairs, East China Key Laboratory of Flower Biology, Key Laboratory of Flower Biology and Germplasm Creation, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, State Forestry and Grassland Administration, 210095, Nanjing, China.
College of Agriculture, Shihezi University, Shihezi, 832000, China.
BMC Genomics. 2023 Feb 21;24(1):82. doi: 10.1186/s12864-023-09176-w.
Tropical water lily is an aquatic plant with high ornamental value, but it cannot overwinter naturally at high latitudes. The temperature drop has become a key factor restricting the development and promotion of the industry.
The responses of Nymphaea lotus and Nymphaea rubra to cold stress were analyzed from the perspective of physiology and transcriptomics. Under the cold stress, Nymphaea rubra had obvious leaf edge curling and chlorosis. The degree of peroxidation of its membrane was higher than that of Nymphaea lotus, and the content of photosynthetic pigments also decreased more than that of Nymphaea lotus. The soluble sugar content, SOD enzyme activity and CAT enzyme activity of Nymphaea lotus were higher than those of Nymphaea rubra. This indicated that there were significant differences in the cold sensitivity of the two varieties. GO enrichment and KEGG pathway analysis showed that many stress response genes and pathways were affected and enriched to varying degrees under the cold stress, especially plant hormone signal transduction, metabolic pathways and some transcription factor genes were from ZAT gene family or WKRY gene family. The key transcription factor ZAT12 protein in the cold stress response process has a CH conserved domain, and the protein is localized in the nucleus. Under the cold stress, overexpression of the NlZAT12 gene in Arabidopsis thaliana increased the expression of some cold-responsive protein genes. The content of reactive oxygen species and MDA in transgenic Arabidopsis thaliana was lower, and the content of soluble sugar was higher, indicating that overexpression of NlZAT12 can improve the cold tolerance of Arabidopsis thaliana.
We demonstrate that ethylene signalling and reactive oxygen species signalling play critical roles in the response of the two cultivars to cold stress. The key gene NlZAT12 for improving cold tolerance was identified. Our study provides a theoretical basis for revealing the molecular mechanism of tropical water lily in response to cold stress.
热带睡莲是一种具有较高观赏价值的水生植物，但在高纬度地区不能自然越冬。温度下降已成为限制产业发展和推广的关键因素。
从生理和转录组学的角度分析了荷花和红睡莲对低温胁迫的响应。在冷胁迫下，红睡莲叶片边缘明显卷曲，出现黄化。其膜的过氧化程度高于荷花，光合色素含量也比荷花下降更多。荷花的可溶性糖含量、SOD 酶活性和 CAT 酶活性均高于红睡莲。这表明两个品种对低温的敏感性存在显著差异。GO 富集和 KEGG 途径分析表明，低温胁迫下许多胁迫响应基因和途径受到不同程度的影响和富集，特别是植物激素信号转导、代谢途径和一些转录因子基因来自 ZAT 基因家族或 WKRY 基因家族。冷胁迫响应过程中的关键转录因子 ZAT12 蛋白具有 CH 保守结构域，该蛋白定位于细胞核内。在低温胁迫下，拟南芥中 NlZAT12 基因的过表达增加了一些冷响应蛋白基因的表达。转基因拟南芥中活性氧和 MDA 的含量较低，可溶性糖的含量较高，表明 NlZAT12 的过表达可以提高拟南芥的耐寒性。
我们证明乙烯信号和活性氧信号在两个品种对低温胁迫的响应中起着关键作用。确定了提高耐寒性的关键基因 NlZAT12。本研究为揭示热带睡莲对低温胁迫的分子机制提供了理论依据。
