Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, J. Plateaustraat 22, B-9000 Ghent, Belgium.
Chemosphere. 2010 Aug;80(9):1014-20. doi: 10.1016/j.chemosphere.2010.05.032. Epub 2010 Jun 26.
Zn exposure of Daphnia magna during one generation has been shown to modulate gene transcription differently in Zn exposed organisms compared to their non-exposed offspring. Here we studied the transcriptional gene regulation with a cDNA microarray in D.magna exposed to Zn for three generations (F0-F2). For the first time molecular effects of multigeneration toxicant exposure in D. magna are described. Out of 73 differentially transcribed genes in the F1Zn exposed generation (compared to the F1 control), only seven genes were also differentially transcribed in the same direction in the F0Zn exposed daphnids (up or down, compared to the F0 control). The majority of the differentially transcribed unigenes in F1Zn exposed daphnids (78%) were not differentially transcribed in the F0Zn exposed organisms. This indicates that Zn exposure affected other molecular pathways in the second exposed generation, although a reduced reproduction and a reduction in juvenile growth were observed in both Zn exposed generations, compared to the respective controls. In the third Zn exposed generation (F2), no reduction in growth or reproduction compared to the control was observed. This acclimation was reflected in a significantly lower number of differentially transcribed genes, compared to the Zn exposed F0 and F1 generations.
一代的 Daphnia magna 中的 Zn 暴露已被证明会使 Zn 暴露的生物体中的基因转录与未暴露的后代不同。在这里，我们使用 cDNA 微阵列研究了 Zn 暴露三代（F0-F2）的 D.magna 的转录基因调控。这是首次描述了 D. magna 中多代毒物暴露的分子效应。在 F1Zn 暴露组（与 F1 对照组相比）中差异转录的 73 个基因中，仅有 7 个基因在 F0Zn 暴露的水蚤中以相同的方向（与 F0 对照组相比）差异转录。在 F1Zn 暴露的水蚤中，大多数差异转录的 unigenes（78%）在 F0Zn 暴露的生物体中没有差异转录。这表明 Zn 暴露在第二代暴露的生物体中影响了其他分子途径，尽管与相应的对照相比，在两个 Zn 暴露的世代中，繁殖减少和幼体生长减少。在第三代 Zn 暴露（F2）中，与对照相比，生长或繁殖没有减少。这种适应反映在与 Zn 暴露的 F0 和 F1 代相比，差异转录的基因数量显著减少。
