Environment Canada, Centre Saint-Laurent, 105 McGill Street, Montreal, QC H2Y 2E7, Canada.
Environment Canada, Centre Saint-Laurent, 105 McGill Street, Montreal, QC H2Y 2E7, Canada.
Chemosphere. 2015 Aug;132:159-65. doi: 10.1016/j.chemosphere.2015.03.028. Epub 2015 Apr 2.
Tris (2-butoxyethyl) phosphate (TBOEP) is an organophosphorous-containing flame retardant (OPFR) of high production volume used in a broad range of applications. The use of TBOEP containing products has resulted in its release and ubiquitous occurrence in the aquatic environment. In this study, Daphnia magna transcriptomic response was measured by microarray to evaluate sublethal effects of TBOEP as part of a multi-level biological approach including specific gene transcription measured by qRT-PCR, enzyme activity, and life-history endpoints (i.e., survival, growth and reproduction). Chronic exposure (21 d) to a range of sublethal concentrations of TBOEP (14.7-1470μgL(-1)) did not impact growth, survival or reproduction, although the number of offspring decreased between the lowest and the highest dose. Gene transcription profiling by microarray analysis revealed that 101 genes were differentially transcribed in response to TBOEP (fold change treated/control ±1, p<0.05). Most of the responding genes were involved in protein metabolism (9), biosynthesis (4) and energy metabolism (6) indicating that TBOEP could have chronic toxic effects on aquatic organisms at sublethal doses by disrupting essential biological pathways. Nine genes were found to be commonly affected by more than one dose, including a gene coding for cathepsin D and multiple isoforms of genes coding for hemoglobin, suggesting potential biomarkers of interest. Microarray results were confirmed by qRT-PCR and measurements at the protein level as cathepsin D enzymatic activity increased significantly in the highest dose treatment. Results highlight the relevance of using the transcriptomic response of D. magna as a first line of evidence to unravel the mode of action of chemicals.
三（2-丁氧基乙基）磷酸酯（TBOEP）是一种高产量的含磷有机阻燃剂（OPFR），广泛应用于各种应用中。TBOEP 含产品的使用导致其释放和在水生环境中普遍存在。在这项研究中，通过微阵列测量大型溞的转录组反应，以评估 TBOEP 的亚致死效应，作为包括通过 qRT-PCR 测量的特定基因转录、酶活性和生活史终点（即生存、生长和繁殖）的多层次生物学方法的一部分。慢性暴露（21 天）于一系列亚致死浓度的 TBOEP（14.7-1470μg/L）不会影响生长、存活或繁殖，尽管最低和最高剂量之间的后代数量减少。通过微阵列分析进行的基因转录谱分析显示，有 101 个基因对 TBOEP 表现出差异转录（处理/对照的倍数变化±1，p<0.05）。大多数响应基因参与蛋白质代谢（9）、生物合成（4）和能量代谢（6），表明 TBOEP 以亚致死剂量对水生生物具有慢性毒性效应，通过破坏基本的生物途径。有 9 个基因受到一个以上剂量的共同影响，包括编码组织蛋白酶 D 的基因和编码血红蛋白的多个基因同工型，这表明它们可能是潜在的感兴趣的生物标志物。微阵列结果通过 qRT-PCR 和蛋白质水平的测量得到了证实，因为在最高剂量处理中，组织蛋白酶 D 酶活性显著增加。结果强调了使用大型溞的转录组反应作为揭示化学物质作用模式的第一线证据的相关性。
