Wang Bin, Fang Ruiqiu, Zhang Guwen, Liu Na, Feng Zhijuan, Bu Yuanpeng, Gong Yaming
Institute of Vegetables, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021, China; Key Laboratory of Vegetable Legumes Germplasm Enhancement and Molecular Breeding in Southern China of Ministry of Agriculture and Rural Affairs, Hangzhou, Zhejiang 310021, China.
Institute of Maize and Featured Upland Crops, Zhejiang Academy of Agricultural Sciences, Dongyang, Zhejiang 322100, China.
Int J Biol Macromol. 2025 May;305(Pt 1):141022. doi: 10.1016/j.ijbiomac.2025.141022. Epub 2025 Feb 13.
Cadmium (Cd) stress is a significant threat to crop production. Abscisic acid (ABA) has been recognized for its ability to mitigate Cd toxicity. However, the underlying regulatory mechanisms governing ABA biosynthesis and its signaling pathway in response to Cd stress remain elusive. Here, we identified a Cd-induced NAC1 transcription factor (Cd-NAC) from vegetable soybean, which played a pivotal role in this process. Overexpression of Cd-NAC in transgenic vegetable soybean roots resulted in enhanced Cd tolerance, manifested by longer roots and higher biomass compared to Cd-NAC knockdown plants. Cd-NAC functions as a nuclear transcription factor that binds directly to the promoters of the 9-cis-epoxycarotenoid dioxygenase coding genes (GmNCED3.1 and GmNCED3.2), thereby activating their transcription and promoting the biosynthesis of ABA. Our findings uncover a crucial molecular mechanism of ABA conferring Cd tolerance in plants, which holds promise for sustainable agricultural production and effective management of this hazardous heavy metal, ultimately contributing to improved environmental management and ecosystem function.
镉（Cd）胁迫是作物生产面临的重大威胁。脱落酸（ABA）因其减轻镉毒性的能力而受到认可。然而，响应镉胁迫时ABA生物合成及其信号通路的潜在调控机制仍不清楚。在此，我们从菜用大豆中鉴定出一种镉诱导的NAC1转录因子（Cd-NAC），它在此过程中发挥了关键作用。与Cd-NAC基因敲低的植株相比，转基因菜用大豆根中Cd-NAC的过表达导致镉耐受性增强，表现为根更长、生物量更高。Cd-NAC作为一种核转录因子，直接与9-顺式环氧类胡萝卜素双加氧酶编码基因（GmNCED3.1和GmNCED3.2）的启动子结合，从而激活它们的转录并促进ABA的生物合成。我们的研究结果揭示了ABA赋予植物镉耐受性的关键分子机制，这为可持续农业生产和有效管理这种有害重金属带来了希望，最终有助于改善环境管理和生态系统功能。
