Endogenous IAA affected fluoranthene accumulation by regulating H+-ATPase and SOD activity in ryegrass

作者：Yuanzhou Xu, Yunyun Li, Zhuoliang Xiao, Xinyue Zhang, Jiaguo Jiao, Huijuan Zhang, Huixin Li, Feng Hu, Li Xu · 发表于：Ecotoxicology and Environmental Safety · 年份：2024 · DOI：10.1016/j.ecoenv.2024.116315 · 被引用次数：5 · 研究领域：Soil Carbon and Nitrogen Dynamics、Plant Stress Responses and Tolerance、Plant responses to elevated CO2

This study explores the role of endogenous indole-3-acetic acid (IAA) in modulating plant responses to pollution stress and its effect on pollutant accumulation, with a focus on fluoranthene (Flu) in ryegrass. To elucidate the mechanism, we employed an IAA promoter (α-aminobutyric acid [α-AB]) and an IAA inhibitor (naphthylphthalamic acid [NPA]) to regulate IAA levels and analyze Flu uptake characteristics. The experimental setup included a Flu treatment group (ryegrass with Flu addition) and a control group (ryegrass without Flu). Our findings demonstrate that Flu treatment enhanced IAA content and plant growth in ryegrass compared to the control. The Flu+AB treatment further enhanced these effects, while the Flu+NPA treatment exhibited a contrasting trend. Moreover, Flu+AB treatment led to increased Flu accumulation, in contrast to the inhibitory effect observed with Flu+NPA treatment. Flu treatment also enhanced the activities of key antioxidant enzymes (SOD, POD, CAT) and increased soluble sugar and protein levels, indicative of enzymatic and nonenzymatic defense responses, respectively. The Flu+AB treatment amplified these responses, whereas the Flu+NPA treatment attenuated them. Significantly, Flu treatment raised H+-ATPase activity compared to the control, an effect further elevated by Flu+AB treatment and diminished by Flu+NPA treatment. A random forest analysis suggested that Flu accumulation dependency varied under different treatments: it relied more on H+-ATPase a...