Connon Richard, Hooper Helen L, Sibly Richard M, Lim Fei-Ling, Heckmann Lars-Henrik, Moore David J, Watanabe Hajime, Soetaert Anneleen, Cook Katie, Maund Steve J, Hutchinson Thomas H, Moggs Jonathan, De Coen Wim, Iguchi Taisen, Callaghan Amanda
School of Biological Sciences, University of Reading, P.O. Box 68, Reading RG6 6BX, UK.
Environ Sci Technol. 2008 Mar 15;42(6):2181-8. doi: 10.1021/es702469b.
DNA microarrays can be used to measure environmental stress responses. If they are to be predictive of environmental impact, we need to determine if altered gene expression translates into negative impacts on individuals and populations. A large cDNA microarray (14000 spots) was created to measure molecular stress responses to cadmium in Daphnia magna,the mostwidely used aquatic indicator species, and relate responses to population growth rate (pgr). We used the array to detect differences in the transcription of genes in juvenile D. magna (24 h old) after 24 h exposure to a control and three cadmium concentrations (6, 20, and 37 microg Cd2+ L(-1)). Stress responses at the population level were estimated following a further 8 days exposure. Pgr was approximately linear negative with increasing cadmium concentration over this range. The microarray profile of gene expression in response to acute cadmium exposure begins to provide an overview of the molecular responses of D. magna, especially in relation to growth and development. Of the responding genes, 29% were involved with metabolism including carbohydrate, fat and peptide metabolism, and energy production, 31% were involved with transcription/translation, while 40% of responding genes were associated with cellular processes like growth and moulting, ion transport, and general stress responses (which included oxidative stress). Our production and application of a large Daphnia magna microarray has shown that measured gene responses can be logically linked to the impact of a toxicant such as cadmium on somatic growth and development, and consequently pgr.
DNA微阵列可用于测量环境应激反应。若要使其能够预测环境影响，我们需要确定基因表达的改变是否会对个体和种群产生负面影响。构建了一个大型cDNA微阵列（14000个点），用于测量水溞（最广泛使用的水生指示物种）对镉的分子应激反应，并将这些反应与种群增长率（pgr）相关联。我们使用该阵列检测幼年水溞（24小时龄）在暴露于对照和三种镉浓度（6、20和37微克Cd2+ L(-1)）24小时后基因转录的差异。在进一步暴露8天后估计种群水平的应激反应。在此范围内，随着镉浓度的增加，pgr大致呈线性负相关。响应急性镉暴露的基因表达微阵列图谱开始提供水溞分子反应的概述，特别是与生长和发育相关的反应。在响应基因中，29%与代谢有关，包括碳水化合物、脂肪和肽代谢以及能量产生，31%与转录/翻译有关，而40%的响应基因与细胞过程有关，如生长和蜕皮、离子运输以及一般应激反应（包括氧化应激）。我们构建并应用大型水溞微阵列表明，所测量的基因反应可以在逻辑上与镉等有毒物质对体细胞生长和发育的影响相关联，进而与pgr相关联。
