Sheader Derek L, Williams Timothy D, Lyons Brett P, Chipman J Kevin
School of Biosciences, The University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Mar Environ Res. 2006 Jul;62(1):33-44. doi: 10.1016/j.marenvres.2006.03.001. Epub 2006 Mar 9.
The monitoring of the impact of chemical pollutants upon marine ecosystems commonly employs a multi-biomarker approach. Functional genomics, using cDNA microarrays, allows for a comprehensive view of how an organism is responding to an exposure, with respect to changes in gene expression. Differentially expressed mRNAs were first isolated from livers of European flounder by means of suppressive, subtractive hybridisation. A clone set containing a total of 284 different potentially differentially expressed mRNAs was produced, of which 84 were tentatively identified. These were combined with previously cloned known stress genes isolated by degenerate PCR to produce a custom 500-clone microarray platform with each clone arrayed to four spots. Subsequent array experiments using cadmium-treated flounder detected up-regulation of 27 transcripts, including Cu/Zn superoxide dismutase, thioredoxin, a peroxiredoxin and a glutathione-S-transferase, reflecting oxidative stress in exposed flounder, while CYP1A expression was down-regulated. These changes were confirmed by real-time PCR. The array experiment highlighted a number of candidate genes for further analysis as potential novel biomarkers of cadmium exposure and demonstrated the applicability of the custom microarray approach in the study of the effects of toxicants.
对化学污染物对海洋生态系统影响的监测通常采用多生物标志物方法。利用cDNA微阵列的功能基因组学能够全面了解生物体在暴露于污染物时基因表达变化方面的反应情况。首先通过抑制性消减杂交从欧洲比目鱼的肝脏中分离出差异表达的mRNA。构建了一个包含总共284个不同的潜在差异表达mRNA的克隆集，其中84个被初步鉴定。将这些与先前通过简并PCR克隆的已知应激基因相结合，制作了一个定制的500克隆微阵列平台，每个克隆排列在四个点上。随后使用镉处理的比目鱼进行的阵列实验检测到27个转录本上调，包括铜/锌超氧化物歧化酶、硫氧还蛋白、一种过氧化物酶和一种谷胱甘肽-S-转移酶，这反映了暴露比目鱼中的氧化应激，而CYP1A的表达则下调。这些变化通过实时PCR得到证实。该阵列实验突出了一些作为镉暴露潜在新型生物标志物进行进一步分析的候选基因，并证明了定制微阵列方法在毒物效应研究中的适用性。
