In the face of escalating environmental challenges, understanding the mechanisms through which plants can resist heavy metal stress is paramount. This study delves into the efficacy of cerium (Ce), a rare earth element, in mitigating copper (Cu) toxicity in Dendrobium nobile Lindl., an orchid plant with significant medicinal and ornamental value. Through a comprehensive experimental approach that encompasses physiological, biochemical, and molecular analyses, we demonstrate that Ce application notably enhances D. nobile's tolerance to Cu stress. The investigation revealed that Ce supplementation significantly ameliorated the adverse effects of Cu on plant growth, evidenced by a notable decrease in Cu accumulation within the plant tissues. At the molecular level, transcriptome sequencing uncovered the upregulation of genes involved in antioxidant defense mechanisms, heavy metal chelation, and stress response signaling pathways. Key findings include the enhanced activities of antioxidant enzymes such as superoxide dismutase, peroxidase, and catalase, alongside an increase in the levels of antioxidants and phytochelatins, which collectively contribute to the detoxification of Cu. Furthermore, Ce was found to influence the subcellular distribution of Cu, promoting its sequestration in less harmful cellular compartments. Our study provides novel insights into the role of Ce in modulating plant responses to heavy metal stress, highlighting its potential as a mitigative agent against Cu toxicity. The elucidation of specific gene regulations and pathway activations offers a foundation for future research aimed at enhancing plant resilience to environmental stresses through biotechnological interventions.

中文翻译：

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转录组学与生理分析相结合，为通过 Ce 调节增强石斛对 Cu 胁迫的恢复能力提供了新的见解


面对不断升级的环境挑战，了解植物抵抗重金属压力的机制至关重要。本研究深入探讨了稀土元素铈 （Ce） 在减轻石斛 （Cu） 毒性方面的功效，林德尔石斛是一种具有重要药用和观赏价值的兰花植物。通过包括生理、生化和分子分析在内的综合实验方法，我们证明 Ce 应用显着增强了 D. nobile 对 Cu 胁迫的耐受性。调查显示，补充 Ce 显着改善了 Cu 对植物生长的不利影响，植物组织内 Cu 积累的显着减少证明了这一点。在分子水平上，转录组测序揭示了参与抗氧化防御机制、重金属螯合和应激反应信号通路的基因上调。主要发现包括超氧化物歧化酶、过氧化物酶和过氧化氢酶等抗氧化酶活性的增强，以及抗氧化剂和植物螯合素水平的增加，它们共同有助于铜的解毒。此外，发现 Ce 影响 Cu 的亚细胞分布，促进其在危害较小的细胞区室中的隔离。我们的研究为 Ce 在调节植物对重金属胁迫的反应中的作用提供了新的见解，突出了其作为缓解 Cu 毒性剂的潜力。阐明特定的基因调控和途径激活为未来的研究奠定了基础，旨在通过生物技术干预增强植物对环境胁迫的适应力。