Graduate Program in Cell and Molecular Biology (PPGBCM), Center for Biotechnology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Laboratory of Plant Molecular Genetics, Embrapa Uva e Vinho, Bento Gonçalves, RS, Brazil; Department of Agronomy and Crop Physiology, Justus Liebig University Giessen, Germany.
J Hazard Mater. 2024 Dec 5;480:136301. doi: 10.1016/j.jhazmat.2024.136301. Epub 2024 Oct 28.
Copper (Cu) is an essential element for plants, participating in photosynthesis, oxidative metabolism and cell wall synthesis. However, excessive Cu may become toxic, as Cu participates in Fenton chemistry and cause oxidative stress. Grapevine (Vitis sp.) is an important perennial crop, used for in natura consumption as well as for wine and juice. Vineyards are susceptible to fungal diseases that are commonly controlled by using Cu-based fungicides, which can lead to Cu accumulation in the soil. Since grape production is based on grafting scions of consumed-friendly varieties onto rootstocks that can withstand soil-borne diseases and stresses, it is important to identify rootstock genotypes that are tolerant to Cu excess. In this work, we compared physiological and molecular responses of four Vitis sp. rootstock genotypes to Cu excess, namely IAC, IBCA, Paulsen and Isabel. While IAC, IBCA, Paulsen were similarly tolerant, Isabel was the most sensitive to Cu excess. IAC and IBCA showed higher Cu accumulation in shoots, suggesting distinct partitioning strategy. We identified core Cu excess-responsive genes in grapevine roots of all four genotypes, including a putative HMA vacuolar Cu transporter and Cu-binding proteins. Genes related to the homeostasis of other elements are altered, such as iron (Fe) and phosphorus (P), suggesting that Cu excess alters the ionome balance. IAC and IBCA had extensive changes in their laccase gene repertoire, suggesting that could be related to the distinct Cu partitioning. Moreover, genes associated specifically with Isabel could be related to the genotype Cu excess sensitivity. Our work provides a valuable dataset for understanding variation in Cu tolerance how roots respond transcriptionally to Cu stress, and provide candidate genes for engineering Cu tolerance in grapevines.
铜（Cu）是植物必需的元素，参与光合作用、氧化代谢和细胞壁合成。然而，过量的 Cu 可能会变得有毒，因为 Cu 参与 Fenton 化学并导致氧化应激。葡萄（Vitis sp.）是一种重要的多年生作物，用于生食以及葡萄酒和果汁。葡萄园易受真菌病害的影响，通常使用含铜杀菌剂来控制这些病害，这可能导致 Cu 在土壤中积累。由于葡萄生产是基于将可食用品种的接穗嫁接到能够耐受土壤传播疾病和胁迫的砧木上，因此确定对 Cu 过量具有耐受性的砧木基因型非常重要。在这项工作中，我们比较了四个葡萄砧木基因型对 Cu 过量的生理和分子反应，即 IAC、IBCA、Paulsen 和 Isabel。虽然 IAC、IBCA 和 Paulsen 表现出相似的耐受性，但 Isabel 对 Cu 过量最为敏感。IAC 和 IBCA 在地上部积累了更高的 Cu，表明它们具有不同的分配策略。我们在所有四个基因型的葡萄根中鉴定了核心 Cu 过量响应基因，包括一个假定的 HMA 液泡 Cu 转运蛋白和 Cu 结合蛋白。与其他元素稳态相关的基因发生改变，如铁（Fe）和磷（P），表明 Cu 过量改变了离子组平衡。IAC 和 IBCA 的漆酶基因库发生了广泛的变化，这表明这可能与不同的 Cu 分配有关。此外，与 Isabel 特异性相关的基因可能与基因型对 Cu 过量的敏感性有关。我们的工作提供了一个有价值的数据集，用于了解 Cu 耐受性的变化以及根系如何在转录水平上对 Cu 胁迫做出反应，并为葡萄中 Cu 耐受性的工程提供候选基因。
