Song Miaoyu, Chen Ziyu, Bahayiding Wupur, Li Jinping, Ma Huiqin, Wang Ziran
College of Horticulture, Yunnan Agricultural University, Kunming, China.
College of Horticulture, China Agricultural University, Beijing, China.
Front Plant Sci. 2024 Nov 26;15:1476126. doi: 10.3389/fpls.2024.1476126. eCollection 2024.
Plant irradiation has been used to induce genetic variation in crop germplasm. However, the underlying mechanisms of plant responses to ionizing radiation stress are still unclear. In plants, reactive oxygen species (ROS) are produced with abiotic stress. Respiratory burst oxidative homologs (Rboh) genes are important regulators of plant ROS stress responses, but little is known of their involvement in the response to ionizing radiation stress. In this study, young branches of L. were irradiated with Co γ-rays and axillary buds were collected after 3- 48 h after irradiation. The differentially expressed genes (DEGs; p< 0.05) detected included an early (6 h) and sustained increase in member of the MAPK signaling pathway. The activities of superoxide dismutase SOD, POD and CAT in fig axillary buds showed a trend of first decrease and then increase with time, while the contents of MDA and H2O2 maintained an overall upward trend. The analysis of differentially expressed genes (DEGs; p < 0.05) indicated an early (6 h) and sustained increase in member of the MAPK signaling pathway. DEGs for glutathione-s-transferase and genes involved in phenylpropanoid and flavonoid biosynthesis pathways were detected at all time points, indicating that γ-irradiation induced an increased capacity for in ROS-scavenging. Substantial changes in the expression of MYB, NAC and bHLH transcription factor family members were also seen to occur within 6 h after irradiation. Taking Rboh-derived ROS signaling pathway as the entry point, the MYB transcription factor, FcMYB3, was identified as an potential upstream regulator of in a yeast one hybrid assay and this interaction verified by LUC and EMSA experiments. The knock-down and overexpression of indicated that FcMYB3 is a positive regulator of ROS accumulation in response to γ-ray radiation stress responses in fig. Our results will provide a better understanding of the mechanisms of radiation tolerance in plant materials.
植物辐照已被用于诱导作物种质的遗传变异。然而，植物对电离辐射胁迫的潜在反应机制仍不清楚。在植物中，活性氧（ROS）是由非生物胁迫产生的。呼吸爆发氧化同源物（Rboh）基因是植物ROS胁迫反应的重要调节因子，但它们在电离辐射胁迫反应中的作用知之甚少。在本研究中，用Co γ射线辐照L.的幼嫩枝条，并在辐照后3 - 48小时收集腋芽。检测到的差异表达基因（DEGs；p<0.05）包括MAPK信号通路成员在早期（6小时）和持续增加。无花果腋芽中超氧化物歧化酶SOD、POD和CAT的活性呈现先下降后上升的趋势，而MDA和H2O2的含量总体呈上升趋势。差异表达基因（DEGs；p < 0.05）分析表明MAPK信号通路成员在早期（6小时）和持续增加。在所有时间点都检测到了谷胱甘肽 - s - 转移酶的DEGs以及参与苯丙烷类和类黄酮生物合成途径的基因，表明γ辐照诱导了ROS清除能力的增强。在辐照后6小时内，MYB、NAC和bHLH转录因子家族成员的表达也发生了显著变化。以Rboh衍生的ROS信号通路为切入点，在酵母单杂交试验中鉴定出MYB转录因子FcMYB3是潜在的上游调节因子，并通过LUC和EMSA实验验证了这种相互作用。FcMYB3的敲低和过表达表明，FcMYB3是无花果响应γ射线辐射胁迫反应中ROS积累的正调节因子。我们的结果将有助于更好地理解植物材料的辐射耐受机制。
