Svendsen C, Owen J, Kille P, Wren J, Jonker M J, Headley B A, Morgan A J, Blaxter M, Stürzenbaum S R, Hankard P K, Lister L J, Spurgeon D J
Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS, United Kingdom.
Environ Sci Technol. 2008 Jun 1;42(11):4208-14. doi: 10.1021/es702745d.
Transcriptional responses of a soil-dwelling organism (the earthworm Lumbricus rubellus) to three chemicals, cadmium (Cd), fluoranthene (FA), and atrazine (AZ), were measured following chronic exposure, with the aim of identifying the nature of any shared transcriptional response. Principal component analysis indicated full or partial separation of control and exposed samples for each compound but not for the composite set of all control and exposed samples. Partial least-squares discriminant analysis allowed separation of the control and exposed samples for each chemical and also for the composite data set, suggesting a common transcriptional response to exposure. Genes identified as changing in expression level (by the least stringent test for significance) following exposure to two chemicals indicated a substantial number of common genes (> 127). The three compound overlapping gene set, however, comprised only 25 genes. We suggest that the low commonality in transcriptional response may be linked to the chronic concentrations (approximately 10% EC50) and chronic duration (28 days) used. Annotations of the three compound overlapping gene set indicated that genes from pathways most often associated with responses to environmental stress, such as heat shock, phase I and II metabolism, antioxidant defense, and cation balance, were not represented. The strongest annotation signature was for genes important in mitochondrial function and energy metabolism.
在长期暴露后，测定了一种土壤栖息生物（赤子爱胜蚓）对三种化学物质镉（Cd）、荧蒽（FA）和莠去津（AZ）的转录反应，目的是确定任何共同转录反应的性质。主成分分析表明，每种化合物的对照样本和暴露样本能完全或部分分离，但所有对照样本和暴露样本的综合数据集则不能。偏最小二乘判别分析能够分离每种化学物质以及综合数据集的对照样本和暴露样本，这表明对暴露存在共同的转录反应。在暴露于两种化学物质后，被鉴定为表达水平发生变化（通过最宽松的显著性检验）的基因显示出大量的共同基因（>127个）。然而，三种化合物的重叠基因集仅包含25个基因。我们认为，转录反应中低共性可能与所使用的慢性浓度（约为半数有效浓度的10%）和慢性持续时间（28天）有关。三种化合物重叠基因集的注释表明，与环境应激反应最常相关的途径中的基因，如热休克、I相和II相代谢、抗氧化防御和阳离子平衡等，并未出现。最强的注释特征是与线粒体功能和能量代谢重要的基因。
