Molecular signatures in rainbow darter (Etheostoma caeruleum) inhabiting an urbanized river reach receiving wastewater effluents
Molecular signatures in rainbow darter (Etheostoma caeruleum) inhabiting an urbanized river reach receiving wastewater effluents
复制标题
DOI：
10.1016/j.aquatox.2014.01.010
复制
发表时间：
2014-03-01
影响因子：
4.5
通讯作者：
Munkittrick, K. R.
中科院分区：
文献类型：
--
作者：
Bahamonde, P. A.;Tetreault, G. R.;Munkittrick, K. R.
彩虹鲈鱼（Etheostoma caeruleum）是一种产于北美的小型底栖鱼类，数量丰富，分布于加拿大安大略省格兰德河流域。在城市废水排放口 (MWWE) 附近的地点，虹鳟鱼表现出雌雄间的雄性特征。 2010年10月，在基奇纳市和滑铁卢市附近格兰德河的3个地点（1个上游参考点和2个下游暴露点）收集了雌性和雄性虹鲈。本研究的主要目标是 (1) 表征整个生物体终点（即条件因子 (K)、肝体指数 (LSI) 和性腺体指数 (GSI)、组织病理学）对 MWWE 的反应，以及 (2) 识别生活在城市废水排放暴露区域的鱼类中，随着暴露于 MWWE 的变化，稳态丰度发生变化的转录本。本研究中测量的基因包括卵黄蛋白原、含有蛋白 9 (sox9) 的 Sry-box、叉头盒 L2 (foxl2)、doublesex 和 mab-3 相关转录因子 1 (dmrt1)、细胞色素 P450、家族 11、亚家族 A、多肽 1 (cyp11a) 以及雌激素 (esr1、esrb) 和雄激素 Car) 受体。条件因素没有变化；然而，与从参考地点采集的鱼类相比，居住在下游环境中的鱼类的 LSI 显着增加，而 GSI 显着下降。在下游地点，男性的双性人发生率很高（接近 70%）；其特征是睾丸内存在卵母细胞。在性腺中，与性别分化相关的基因存在性别特异性差异； dmrt1 仅在男性中表达，而与男性相比，foxl2 和 sox9 在女性中高度表达。女性中 ar 和 esr1 的表达水平高于男性。相反，esrb 在性别之间或位点之间没有差异表达。不同地点之间性别内调查的基因没有检测到差异。这项研究首次报告了彩虹镖鲈的基因表达变化，重点关注性别之间转录本丰度的差异以及这些变化与 MWWE 暴露的关系。正在研究分子方法在现场生态毒理学中的潜在应用，并且需要对环境监测计划中的相关哨兵物种进行分子生物测定，以更好地了解人为影响对河流系统中面临风险的物种的影响。 (C) 2014 Elsevier B.V. 保留所有权利。
Rainbow darter (Etheostoma caeruleum) is a small benthic fish species found in North America that are abundant and distributed throughout the Grand River watershed, ON, Canada. Rainbow darter exhibit intersex in males at sites adjacent to municipal wastewater effluents (MWWE). In October 2010, female and male rainbow darter were collected at 3 sites (1 upstream reference and 2 downstream exposed sites) in the Grand River near the cities of Kitchener and Waterloo. The primary objectives of this research were (1) to characterize the responses of whole organism endpoints (i.e. condition factor (K), liversomatic (LSI) and gonadosomatic index (GSI), histopathology) to MWWEs and (2) to identify transcripts showing altered steady state abundance with exposure to MWWE in fish inhabiting municipal wastewater effluent-exposed areas. Genes measured in this study included vitellogenin, Sry-box containing protein 9 (sox9), forkhead box L2 (foxl2), doublesex and mab-3 related transcription factor 1 (dmrt1), cytochrome P450, family 11, subfamily A, polypeptide 1 (cyp11a) as well as estrogen (esr1, esrb) and androgen Car) receptors. There were no changes in condition factor; however, there was a significant increase in LSI and a decrease in GSI in fish inhabiting downstream environments when compared with fish collected from the reference site. Males had a high incidence (similar to 70%) of intersex in downstream sites; characterized by the presence of oocytes within the testis. In the gonad, there were sex specific differences for genes related to sexual differentiation; dmrt1 was only expressed in males whereas foxl2 and sox9 were highly expressed in females compared to males. Expression levels of ar and esr1 were higher in females than males. Conversely, esrb was not differentially expressed between sexes or among sites. There were no differences detected for the genes investigated within sex among sites. This study is the first to report on gene expression changes in the rainbow darter, with emphasis on the differences in transcript abundance between sexes and how these changes relate to exposures to MWWEs. Molecular approaches are being investigated for their potential application to field ecotoxicology, and molecular bioassays for relevant, sentinel species in environmental monitoring programs are required to better understand the impact of anthropogenic impacts on species at risk in river systems. (C) 2014 Elsevier B.V. All rights reserved.