The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China.
The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China.
Aquat Toxicol. 2018 Nov;204:59-69. doi: 10.1016/j.aquatox.2018.08.020. Epub 2018 Aug 28.
In order to monitor the pollution of polycyclic aromatic hydrocarbons (PAHs) in the seawater environment, screening biomarkers capable of monitoring PAHs is the focus of many studies. The transcriptomic profiles of the digestive gland tissue from the R. philippinarum groups after the exposure to BaP (4 μg/L) at four time points (0, 0.5, 6 and 15 days) were investigated to globally screen the key genes and pathways involved in the responses to short-term stress and long-term adaptation of BaP resistance. By comparative transcriptome analysis, 233, 282 and 58 differentially expressed genes (DEGs) were identified at 0.5 day, 6 day and 15 day (vs 0 day). The differential expression genes were related to stress response, detoxification metabolic process and innate immunity. DEGs of each group at different stages were clustered in six profiles based on gene expression pattern. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis were used on all genes to determine the biological functions and processes. We selected Multidrug resistance protein 3 (MRP3), transcriptional regulator ATRX-like isoform X2 (ATRX) as biomarker indicator genes for short-term pollution monitoring and NADH dehydrogenase [ubiquinone] 1 (NQO1), Complement C1q-like protein 4 (C1q), Glutathione-S-transferase theta (GST), E3 ubiquitin-protein ligase (E3) for long-term pollution monitoring based on the different expression patterns and the function in detoxification and antioxidant defense system. Besides, the expression of seven genes was measured through Quantitative real-time PCR (qPCR) according to their gene expression patterns which was confirmed by the DGE analysis. Taken together, adoption of transcriptomic analysis to explore the bivalves' mRNA abundance changes and detoxification metabolic mechanism under the BaP stress at different time points can aid the development of sensitive and informed molecular endpoints for application towards ecotoxicogenomic monitoring of bivalves.
为了监测海水中多环芳烃（PAHs）的污染，筛选能够监测 PAHs 的生物标志物是许多研究的重点。本研究采用高通量转录组测序技术，以菲律宾蛤仔（Ruditapes philippinarum）为实验对象，在暴露于苯并[a]芘（BaP，4μg/L）后四个时间点（0、0.5、6 和 15 天）检测其消化腺组织的转录组谱，以全面筛选参与短期胁迫反应和长期 BaP 抗性适应的关键基因和途径。通过比较转录组分析，在 0.5 天、6 天和 15 天（与 0 天相比）分别鉴定出 233、282 和 58 个差异表达基因（DEGs）。差异表达基因与应激反应、解毒代谢过程和固有免疫有关。基于基因表达模式，将不同阶段每组的差异表达基因聚类为六个谱。基于所有基因的基因本体（GO）和京都基因与基因组百科全书（KEGG）通路分析，确定生物功能和过程。我们选择多药耐药蛋白 3（MRP3）、转录调节因子 ATRX 样异构体 X2（ATRX）作为短期污染监测的生物标志物指示基因，选择 NADH 脱氢酶[泛醌]1（NQO1）、补体 C1q 样蛋白 4（C1q）、谷胱甘肽 S-转移酶 theta（GST）、E3 泛素蛋白连接酶（E3）作为长期污染监测的生物标志物，基于它们的不同表达模式以及在解毒和抗氧化防御系统中的功能。此外，根据 DGE 分析的结果，根据其基因表达模式通过定量实时 PCR（qPCR）测量了七个基因的表达。综上所述，采用转录组分析方法，探讨了在不同时间点苯并[a]芘胁迫下双壳贝类 mRNA 丰度变化和解毒代谢机制，为贝类生态毒理基因组监测中敏感和信息丰富的分子终点的发展提供了帮助。
