Liu Jia, Shi Kun, Wang Shaopeng, Zhu Jiahao, Wang Xijuan, Hong Jun, Wang Zan
College of Grass Science and Technology, China Agricultural University, Beijing, 100193, China.
National Animal Husbandry Services, Beijing, 100125, China.
Plant Physiol Biochem. 2023 Oct;203:107999. doi: 10.1016/j.plaphy.2023.107999. Epub 2023 Sep 2.
Cytochrome P450 (CYP450) family proteins play key roles in plant growth, development, stress responses, and other physiological processes. Here, we cloned the cytochrome P450 gene MsCYP71 in alfalfa and found that the expression of MsCYP71 was induced by drought stress. Silencing the MsCYP71 gene using virus-induced gene silencing technology significantly decreased the drought resistance of alfalfa, as indicated by their lower relative water content, net photosynthetic rate, and chlorophyll fluorescence maximum (Fm); further, the heterologous overexpression of MsCYP71 in tobacco significantly enhanced the drought resistance and Fm of transgenic tobacco. Furthermore, the expression of MsCYP71 across 45 alfalfa accessions under drought stress was investigated. A significant positive correlation between drought resistance and MsCYP71 expression was observed. The 45 alfalfa accessions were clustered into four groups, and drought resistance, Fm, and MsCYP71 were higher in group I than in the other groups, indicating that group I accessions can be used as candidate germplasm resources for the breeding of drought-resistant alfalfa varieties. Overall, our findings indicated that MsCYP71 is a positive regulator of drought resistance in alfalfa, and its expression can be used to evaluate the drought resistance of alfalfa.
细胞色素P450（CYP450）家族蛋白在植物生长、发育、应激反应及其他生理过程中发挥关键作用。在此，我们克隆了苜蓿中的细胞色素P450基因MsCYP71，并发现MsCYP71的表达受干旱胁迫诱导。利用病毒诱导基因沉默技术沉默MsCYP71基因显著降低了苜蓿的抗旱性，表现为其相对含水量、净光合速率和叶绿素荧光最大值（Fm）较低；此外，MsCYP71在烟草中的异源过表达显著增强了转基因烟草的抗旱性和Fm。此外，研究了45份苜蓿种质在干旱胁迫下MsCYP71的表达情况。观察到抗旱性与MsCYP71表达之间存在显著正相关。45份苜蓿种质被聚类为四组，I组的抗旱性、Fm和MsCYP71均高于其他组，表明I组种质可作为抗旱苜蓿品种选育的候选种质资源。总体而言，我们的研究结果表明MsCYP71是苜蓿抗旱性的正调控因子，其表达可用于评估苜蓿的抗旱性。
