School of Environmental Science and Engineering, Tianjin University, 92 Weijin Road, Tianjin, 300072, China.
Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, 154 Anshan Road, Tianjin, 300070, China.
Environ Pollut. 2021 Aug 1;282:117032. doi: 10.1016/j.envpol.2021.117032. Epub 2021 Apr 2.
Among emerging organic contaminants (EOCs), triclosan (TCS) is an antibacterial agent and frequently detected in sludge. In this study, RNA sequencing (RNA-seq) was used to obtain the first transcriptomic profile of tobacco with TCS treatment in comparison with control. The results of transcriptome profiling indicated that salicylic acid (SA) signalling pathway actively participated in the tobacco's response to TCS treatment. The accumulation of endogenous SA in transgene tobacco lines transformed with a homologous gene of SA binding protein (LcSABP) was significantly enhanced. The resistance of transgenic tobacco lines to TCS was markedly enhanced revealed by morphological and physiological indexes while the total Chl level and P of transgenic individuals showed about 180% and 250% higher than that of WT on average, and the accumulation of HO and O induced by TCS in SABP overexpressing tobacco was 35.3%-37.3% and 53.0%-56.0% lower than that of WT. In order to further explore the mechanism of TCS tolerance in transgenic plants, RNA-seq was then performed to obtain the second transcriptomic profile between wild type and transgenic samples with TCS exposure. The results indicated that differentially expressed genes (DEGs) were most highly enriched in MAPK signalling pathway, amino acid synthesis pathway and plant hormone transduction pathway. Especially, genes encoding key proteins such as cytochrome P450, laccase, peroxidase, glycosyl transferase, glutathione S-transferase and ATP-binding cassette were considered to be related to the increased tolerance ability of transgenic tobacco to the treatment of TCS stress. This research will likely provide novel insights into the molecular mechanism of SA-mediated amelioration of TCS stress on tobacco.
在新兴的有机污染物 (EOCs) 中，三氯生 (TCS) 是一种抗菌剂，经常在污泥中检测到。在这项研究中，使用 RNA 测序 (RNA-seq) 获得了烟草在 TCS 处理下的第一个转录组图谱，与对照进行了比较。转录组谱分析的结果表明，水杨酸 (SA) 信号通路积极参与了烟草对 TCS 处理的反应。用同源基因的 SA 结合蛋白 (LcSABP) 转化的转基因烟草系中内源 SA 的积累显著增强。通过形态和生理指标，转基因烟草系对 TCS 的抗性明显增强，而转基因个体的总 Chl 水平和 P 平均比 WT 高约 180%和 250%，并且 SABP 过表达烟草中 HO 和 O 因 TCS 诱导的积累比 WT 低 35.3%-37.3%和 53.0%-56.0%。为了进一步探讨转基因植物对 TCS 耐受性的机制，然后进行 RNA-seq 以获得暴露于 TCS 时野生型和转基因样品之间的第二个转录组图谱。结果表明，差异表达基因 (DEGs) 在 MAPK 信号通路、氨基酸合成途径和植物激素转导途径中高度富集。特别是，编码细胞色素 P450、漆酶、过氧化物酶、糖基转移酶、谷胱甘肽 S-转移酶和 ATP 结合盒等关键蛋白的基因被认为与转基因烟草对 TCS 胁迫处理的耐受性增加能力有关。这项研究可能为 SA 介导的改善烟草 TCS 胁迫的分子机制提供新的见解。
