Department of Life Sciences, Changzhi University, Changzhi 046011, China.
School of Life Science, Shanxi Normal University, Taiyuan 030031, China.
Genomics. 2024 Sep;116(5):110926. doi: 10.1016/j.ygeno.2024.110926. Epub 2024 Aug 22.
During sunflower growth, cold waves often occur and impede plant growth. Therefore, it is crucial to study the underlying mechanism of cold resistance in sunflowers. In this study, physiological analysis revealed that as cold stress increased, the levels of ROS, malondialdehyde, ascorbic acid, and dehydroascorbic acid and the activities of antioxidant enzymes increased. Transcriptomics further identified 10,903 DEGs between any two treatments. Clustering analysis demonstrated that the expression of MYB44a, MYB44b, MYB12, bZIP2 and bZIP4 continuously upregulated under cold stress. Cold stress can induce ROS accumulation, which interacts with hormone signals to activate cold-responsive transcription factors regulating target genes involved in antioxidant defense, secondary metabolite biosynthesis, starch and sucrose metabolism enhancement for improved cold resistance in sunflowers. Additionally, the response of sunflowers to cold stress may be independent of the CBF pathway. These findings enhance our understanding of cold stress resistance in sunflowers and provide a foundation for genetic breeding.
在向日葵生长过程中，经常会出现寒潮，阻碍植物生长。因此，研究向日葵的抗寒机制至关重要。本研究通过生理分析发现，随着冷胁迫的增加，ROS、丙二醛、抗坏血酸、脱氢抗坏血酸的水平和抗氧化酶的活性增加。转录组学进一步在任意两种处理之间鉴定出 10903 个 DEGs。聚类分析表明，在冷胁迫下，MYB44a、MYB44b、MYB12、bZIP2 和 bZIP4 的表达持续上调。冷胁迫会诱导 ROS 积累，与激素信号相互作用，激活冷响应转录因子，调节参与抗氧化防御、次生代谢物生物合成、淀粉和蔗糖代谢增强的靶基因，从而提高向日葵的抗寒性。此外，向日葵对冷胁迫的反应可能不依赖于 CBF 途径。这些发现提高了我们对向日葵抗寒能力的理解，为遗传育种提供了基础。
