Jeffrey Jennifer D, Carlson Hunter, Wrubleski Dale, Enders Eva C, Treberg Jason R, Jeffries Ken M
Department of Biological Sciences, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 Canada.
Institute for Wetland and Waterfowl Research, Ducks Unlimited Canada, Stonewall, Manitoba, R0C 2Z0 Canada.
Conserv Physiol. 2020 Dec 15;8(1):coaa099. doi: 10.1093/conphys/coaa099. eCollection 2020.
Molecular techniques have been increasingly used in a conservation physiology framework to provide valuable information regarding the mechanisms underlying responses of wild organisms to environmental and anthropogenic stressors. In the present study, we developed a reference gill transcriptome for walleye (), allowing us to pair a gene-suite approach (i.e. multiple genes across multiple cellular processes) with multivariate statistics to examine the physiological status of wild-caught walleye. For molecular analyses of wild fish, the gill is a useful target for conservation studies, not only because of its importance as an indicator of the physiological status of fish but also because it can be biopsied non-lethally. Walleye were non-lethally sampled following short- (1.5 months) and long-term (3.5 months) confinement in the Delta Marsh, which is located south of Lake Manitoba in Manitoba, Canada. Large-bodied walleye are confined in the Delta Marsh from late April to early August by exclusion screens used to protect the marsh from invasive common carp (), exposing fish to potentially stressful water quality conditions. Principal components analysis revealed patterns of transcript abundance consistent with exposure of fish to increasingly high temperature and low oxygen conditions with longer holding in the marsh. For example, longer-term confinement in the marsh was associated with increases in the mRNA levels of heat shock proteins and a shift in the mRNA abundance of aerobic to anaerobic metabolic genes. Overall, the results of the present study suggest that walleye confined in the Delta Marsh may be exhibiting sub-lethal responses to high temperature and low oxygen conditions. These results provide valuable information for managers invested in mediating impacts to a local species of conservation concern. More broadly, we highlight the usefulness of pairing transcriptomic techniques with multivariate statistics to address potential confounding factors that can affect measured physiological responses of wild-caught fish.
分子技术在保护生理学框架中的应用越来越广泛，可为野生生物对环境和人为压力源的反应机制提供有价值的信息。在本研究中，我们开发了大眼狮鲈的鳃转录组参考序列，这使我们能够将基因组合方法（即跨多个细胞过程的多个基因）与多元统计相结合，以检查野生捕获的大眼狮鲈的生理状态。对于野生鱼类的分子分析，鳃是保护研究的一个有用目标，这不仅是因为它作为鱼类生理状态指标的重要性，还因为可以通过非致死性活检获取样本。在加拿大曼尼托巴省曼尼托巴湖以南的三角洲沼泽中，对大眼狮鲈进行了短期（约1.5个月）和长期（约3.5个月）的圈养后，进行了非致死性采样。大型大眼狮鲈在4月下旬至8月初被围网限制在三角洲沼泽中，这些围网用于保护沼泽免受入侵的鲤鱼的侵害，这使鱼类暴露于潜在的应激水质条件下。主成分分析揭示了转录本丰度模式，这些模式与鱼类在沼泽中停留时间越长，暴露于越来越高的温度和低氧条件下的情况一致。例如，在沼泽中停留时间越长，热休克蛋白的mRNA水平就会增加，有氧代谢基因向无氧代谢基因的mRNA丰度也会发生变化。总体而言，本研究结果表明，被限制在三角洲沼泽中的大眼狮鲈可能正在对高温和低氧条件表现出亚致死反应。这些结果为致力于减轻对当地受保护物种影响的管理者提供了有价值的信息。更广泛地说，我们强调了将转录组技术与多元统计相结合以解决可能影响野生捕获鱼类测量生理反应的潜在混杂因素的有用性。
