Transcriptomic response of Arabidopsis thaliana (L.) Heynh. roots to ibuprofen

Surface waters in urban areas are contaminated by ibuprofen (IBP), a popular and extensively used anti-inflammatory drug. In this study, we investigated the transcriptomic response in Arabidopsis thaliana (L.) Heynh. roots with the aim of revealing genes that are potentially involved in IBP detoxification and elucidating the effect of IBP on plants. IBP upregulated 63 and downregulated 38 transcripts (p-value < 0.1, fold change ≥2) after 2-day exposure to a 5-µM (1.03 mg/L) concentration of IBP under hydroponic conditions. Although the IBP concentration used in the experiment was highly relative to the concentrations found in rivers and wastewater, the number of genes with transcriptional changes was relatively low. The upregulation of cytochrome P450s, glutathione S-transferases, and UDP-glycosyltransferases indicates the occurrence of IBP oxidation in the first phase, followed by conjugation with glutathione and sugar in the second detoxification phase. ABC transporters could be involved in the transport of IBP and its metabolites. The identification of genes potentially involved in IBP detoxification could be useful in an IBP phytoremediation approach.

城市地表水体已被布洛芬（ibuprofen，IBP）污染，该物质是一款临床应用广泛的抗炎药物。本研究以拟南芥（Arabidopsis thaliana (L.) Heynh.）的根部为实验材料，分析其转录组响应，旨在挖掘潜在参与布洛芬解毒过程的基因，并阐明布洛芬对植物的影响。在水培培养条件下，以浓度为5 μmol/L（1.03 mg/L）的布洛芬处理拟南芥2天后，布洛芬可使63个转录本表达上调、38个转录本表达下调（p值 < 0.1，倍数变化≥2）。尽管本实验所用的布洛芬浓度远高于河流与废水中的实际检出浓度，但发生转录水平变化的基因数量仍相对较少。细胞色素P450、谷胱甘肽S-转移酶及UDP-糖基转移酶的表达上调，提示布洛芬在第一阶段发生氧化反应，随后在第二解毒阶段与谷胱甘肽及糖类结合。ATP结合盒转运蛋白（ABC transporters）可能参与布洛芬及其代谢产物的跨膜转运。本研究鉴定出的潜在参与布洛芬解毒的基因，可为布洛芬的植物修复技术提供理论参考。