Growth and quantitative PCR data from oysters (Crassotrea virginica) deployed along the northern Gulf of Mexico coast, May 2010 - June 2011

The Deepwater Horizon oil spill (April 20, 2010 to July 15, 2010) was responsible for the release of ~ 4 to 5 million barrels of crude oil in to the Gulf of Mexico and contaminating the coastline of Louisiana, Mississippi, Alabama and Florida. The aryl hydrocarbon receptor (AHR) pathway is considered to be the ‘master regulator’ of the molecular response to hydrocarbon exposure. In vertebrates, the AHR pathway regulates a battery of phase I and phase II metabolic genes responsible for the biotransformation of hydrocarbons to water soluble, and potentially less toxic metabolites. The AHR pathway is also known to crosstalk with the NRF2 pathway (‘master regulator’ of the oxidative stress response) to assist in ameliorating oxidative stress caused by hydrocarbon biotransformation. The classic molecular biomarker for vertebrate hydrocarbon exposure is induction of the cytochrome P450 1A (CYP1A) gene regulated by the AHR. However, these pathways (AHR and NRF2) are best characterized in vertebrate models and any conservation of function between vertebrates and invertebrates is poorly understood. To investigate the activation of these pathways in a classic invertebrate monitoring species, hatchery raised oysters (Crassostrea virginica) were routinely deployed over the period of one year at three different oysters reefs near Mobile Bay, AL – Grand Bay, Fort Morgan and Orange Beach. Oysters were deployed for a period of two months and sample five times during the 12 month monitoring program – May, August and November of 2010, and Feb and May of 2011. After collection of the oysters at the end of each deployment, gill and digestive gland tissue was removed by dissection and Total RNA was isolated from each individual tissue. Gene expression profiling of selected biomarkers consisting with hydrocarbon toxicity was performed on six biological replicates (per deployment site and collection date), with each replicate consisting of pooled equivalent amounts of RNA from four individual oysters.2010年4月20日至7月15日发生的深水地平线（Deepwater Horizon）原油泄漏事件，共向墨西哥湾释放了约400万至500万桶原油，污染了路易斯安那州、密西西比州、阿拉巴马州及佛罗里达州的海岸线。芳香烃受体（aryl hydrocarbon receptor, AHR）通路被认为是烃类暴露分子应答的‘主调控通路’。在脊椎动物中，AHR通路调控一系列I相和II相代谢基因，这些基因负责将烃类生物转化为水溶性且毒性可能更低的代谢产物。已知AHR通路还可与NRF2通路（氧化应激应答的‘主调控通路’）发生串扰，以缓解烃类生物转化所引发的氧化应激。脊椎动物烃类暴露的经典分子生物标志物，是AHR调控的细胞色素P450 1A（cytochrome P450 1A, CYP1A）基因的诱导表达。然而，目前对AHR与NRF2通路的研究多集中于脊椎动物模型，脊椎动物与无脊椎动物之间的功能保守性仍不甚明确。为探究该通路在经典无脊椎动物监测物种中的激活情况，本研究将孵化场繁育的美洲牡蛎（Crassostrea virginica）于为期一年的周期内，常规部署在阿拉巴马州莫比尔湾附近的三处牡蛎礁——大湾（Grand Bay）、摩根堡（Fort Morgan）与奥兰治海滩（Orange Beach）。本次12个月的监测计划中，牡蛎每次部署时长为2个月，共采样5次：2010年5月、8月、11月，以及2011年2月与5月。每次部署结束后采集牡蛎，通过解剖获取其鳃与消化腺组织，并从每份组织中提取总RNA（Total RNA）。针对与烃类毒性相关的选定生物标志物，我们对每个部署位点与采样日期对应的6个生物学重复样本进行了基因表达谱分析；每个重复样本均混合了4只牡蛎的等量RNA。