South Carolina Department of Natural Resources, Charleston, SC 29422-2559, USA.
Mol Ecol. 2011 Apr;20(7):1431-49. doi: 10.1111/j.1365-294X.2011.05018.x. Epub 2011 Feb 24.
Understanding the mechanisms by which organisms adapt to environmental conditions is a fundamental question for ecology and evolution. In this study, we evaluate changes in gene expression of a marine mollusc, the eastern oyster Crassostrea virginica, associated with the physico-chemical conditions and the levels of metals and other contaminants in their environment. The results indicate that transcript signatures can effectively disentangle the complex interactive gene expression responses to the environment and are also capable of disentangling the complex dynamic effects of environmental factors on gene expression. In this context, the mapping of environment to gene and gene to environment is reciprocal and mutually reinforcing. In general, the response of transcripts to the environment is driven by major factors known to affect oyster physiology such as temperature, pH, salinity, and dissolved oxygen, with pollutant levels playing a relatively small role, at least within the range of concentrations found in the studied oyster habitats. Further, the two environmental factors that dominate these effects (temperature and pH) interact in a dynamic and nonlinear fashion to impact gene expression. Transcriptomic data obtained in our study provide insights into the mechanisms of physiological responses to temperature and pH in oysters that are consistent with the known effects of these factors on physiological functions of ectotherms and indicate important linkages between transcriptomics and physiological outcomes. Should these linkages hold in further studies and in other organisms, they may provide a novel integrated approach for assessing the impacts of climate change, ocean acidification and anthropogenic contaminants on aquatic organisms via relatively inexpensive microarray platforms.
理解生物适应环境条件的机制是生态学和进化学的一个基本问题。在这项研究中，我们评估了海洋软体动物东方牡蛎（Crassostrea virginica）的基因表达变化，这些变化与环境中的理化条件以及金属和其他污染物的水平有关。结果表明，转录特征可以有效地分离出环境对基因表达的复杂相互作用的基因表达反应，并且还能够分离环境因素对基因表达的复杂动态影响。在这种情况下，环境到基因和基因到环境的映射是相互的，相互加强的。一般来说，转录本对环境的反应是由已知影响牡蛎生理的主要因素驱动的，如温度、pH 值、盐度和溶解氧，而污染物水平的作用相对较小，至少在研究牡蛎栖息地中发现的浓度范围内是如此。此外，主导这些效应的两个环境因素（温度和 pH 值）以动态和非线性的方式相互作用，影响基因表达。我们研究中获得的转录组数据提供了对牡蛎对温度和 pH 值的生理反应机制的深入了解，这些机制与这些因素对变温动物生理功能的已知影响一致，并表明转录组学和生理结果之间存在重要联系。如果这些联系在进一步的研究和其他生物体中成立，它们可能为通过相对廉价的微阵列平台评估气候变化、海洋酸化和人为污染物对水生生物的影响提供一种新的综合方法。
