Biology, The Life Science Center, School of Science and Technology, Örebro University, SE-701 82, Örebro, Sweden.
, Örebro, Sweden.
BMC Genomics. 2024 Aug 19;25(1):790. doi: 10.1186/s12864-024-10701-8.
Metal contamination of aquatic environments remains a major concern due to their persistence. The water flea Daphnia magna is an important model species for metal toxicity studies and water quality assessment. However, most research has focused on physiological endpoints such as mortality, growth, and reproduction in laboratory settings, as well as neglected toxicogenomic responses. Copper (Cu) and zinc (Zn) are essential trace elements that play crucial roles in many biological processes, including iron metabolism, connective tissue formation, neurotransmitter synthesis, DNA synthesis, and immune function. Excess amounts of these metals result in deviations from homeostasis and may induce toxic responses. In this study, we analyzed Daphnia magna transcriptomic responses to IC levels of Cu (120 µg/L) and Zn (300 µg/L) in environmental water obtained from a pristine lake with adjusted water hardness (150 mg/L CaCO). The study was carried out to gain insights into the Cu and Zn regulated stress response mechanisms in Daphnia magna at transcriptome level. A total of 2,688 and 3,080 genes were found to be differentially expressed (DEG) between the control and Cu and the control and Zn, respectively. There were 1,793 differentially expressed genes in common for both Cu and Zn, whereas the number of unique DEGs for Cu and Zn were 895 and 1,287, respectively. Gene ontology and KEGG pathways enrichment were carried out to identify the molecular functions and biological processes affected by metal exposures. In addition to well-known biomarkers, novel targets for metal toxicity screening at the genomic level were identified.
由于其持久性，水生环境中的金属污染仍然是一个主要关注点。大型水蚤（Daphnia magna）是金属毒性研究和水质评估的重要模式生物。然而，大多数研究都集中在实验室环境中生理终点，如死亡率、生长和繁殖，以及忽视了毒理基因组学反应。铜（Cu）和锌（Zn）是必需的微量元素，在许多生物过程中发挥着关键作用，包括铁代谢、结缔组织形成、神经递质合成、DNA 合成和免疫功能。这些金属的过量会导致体内平衡的偏离，并可能引起毒性反应。在这项研究中，我们分析了大型水蚤转录组对环境水中 IC 水平的 Cu（120μg/L）和 Zn（300μg/L）的反应，这些环境水来自一个原始湖泊，水硬度（150mg/L CaCO3）经过调整。这项研究旨在深入了解在转录组水平上大型水蚤中 Cu 和 Zn 调节的应激反应机制。在对照组和 Cu 组以及对照组和 Zn 组之间分别发现了 2688 个和 3080 个差异表达基因（DEG）。在 Cu 和 Zn 之间有 1793 个共同差异表达基因，而 Cu 和 Zn 各自特有的差异表达基因数量分别为 895 和 1287。进行了基因本体和 KEGG 途径富集，以确定受金属暴露影响的分子功能和生物过程。除了众所周知的生物标志物外，还确定了在基因组水平上进行金属毒性筛选的新靶标。
