Shi Pixiu, Liu Yinan, Wang Yu, Li Ling, Liang Yuchen, Lin Haijiao, Yuan Zening, Ding Guohua
College of Life Science and Technology, Harbin Normal University, Harbin, China.
Heilongjiang Provincial Key Laboratory of Plant Biology in Ordinary Colleges and Universities, Harbin Normal University, Harbin, China.
BMC Plant Biol. 2024 Dec 27;24(1):1263. doi: 10.1186/s12870-024-05991-9.
Lavandula angustifolia Mill., a valuable aromatic plant, often encounters low temperature stress during its growth in Northeast China. Understanding the mechanisms behind its resistance to low temperatures is essential for enhancing this trait. Flavonoids play a vital role as stress-resistant compounds, significantly contributing to plants' responses to low-temperature stress. However, the molecular mechanism governing flavonoid biosynthesis in L. angustifolia under low-temperature stress is remains inadequately understood.
In this study, the physiological indexes, metabolome, and transcriptome of L. angustifolia were studied under temperatures of 30 °C, 20 °C, 10 °C, and 0 °C. The activities of peroxidase (POD) and superoxide dismutase (SOD) were notably the highest at 0 ℃, demonstrating optimal scavenging of reactive oxygen species (ROS). Among the 1150 metabolites analyzed, 52 flavonoid differential expression metabolites (DEMs) significantly increased at 10 °C and 0 °C. Furthermore, 55 differential expression genes (DEGs) involved in the flavonoid biosynthesis pathway showed significant up-regulation as the temperature dropped from 30 °C to 0 °C, indicating their role in positively regulating flavonoid biosynthesis under low temperatures. The flavonoid biosynthetic pathway was established based on key DEGs, including LaPAL-5, LaPAL-11, LaC4H-2, LaHCT, LaC3'H-4, LaCHS, LaF3PH-3, LaCCoAOMT-2, LaCCoAOMT-3, and LaDFR. Conserved domains predicted in 10 key proteins were identified as being responsible for catalytic functions that promote flavonoid biosynthesis under low temperatures. The synergistic enhancement between flavonoid DEMs and antioxidant enzymes was found to significantly contribute to the cold resistance of L.angustifolia.
The findings of this study provide a valuable reference for understanding the molecular regulation of L. angustifolia in response to low temperatures, laying a crucial foundation for future molecular breeding efforts aimed at developing cold-resistant varieties.
薰衣草是一种珍贵的芳香植物，在中国东北地区生长期间经常遭遇低温胁迫。了解其抗低温的机制对于增强这一特性至关重要。黄酮类化合物作为抗逆化合物发挥着重要作用，对植物应对低温胁迫有显著贡献。然而，低温胁迫下薰衣草中黄酮类生物合成的分子机制仍未得到充分了解。
本研究在30℃、20℃、10℃和0℃温度条件下，对薰衣草的生理指标、代谢组和转录组进行了研究。过氧化物酶（POD）和超氧化物歧化酶（SOD）的活性在0℃时显著最高，表明对活性氧（ROS）的清除效果最佳。在分析的1150种代谢物中，52种黄酮类差异表达代谢物（DEM）在10℃和0℃时显著增加。此外，随着温度从30℃降至0℃，参与黄酮类生物合成途径的55个差异表达基因（DEG）显著上调，表明它们在低温下对黄酮类生物合成起正调控作用。基于关键DEG建立了黄酮类生物合成途径，包括LaPAL - 5、LaPAL - 11、LaC4H - 2、LaHCT、LaC3'H - 4、LaCHS、LaF3PH - 3、LaCCoAOMT - 2、LaCCoAOMT - 3和LaDFR。在10种关键蛋白中预测的保守结构域被确定负责促进低温下黄酮类生物合成的催化功能。发现黄酮类DEM与抗氧化酶之间的协同增强显著有助于薰衣草的抗寒性。
本研究结果为理解薰衣草对低温响应的分子调控提供了有价值的参考，为未来培育抗寒品种的分子育种工作奠定了关键基础。
