The copepod Tigriopus: A promising marine model organism for ecotoxicology and environmental genomics

• Published in: Aquatic toxicology Vol. 83; no. 3; pp. 161 - 173
• Main Authors: Raisuddin, Sheikh, Kwok, Kevin W.H., Leung, Kenneth M.Y., Schlenk, Daniel, Lee, Jae-Seong
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 20.07.2007; Elsevier Science
• Subjects: animal models; Animal, plant and microbial ecology; Animals; Applied ecology; aquatic invertebrates; Bioassay; bioassays; Biological and medical sciences; Biological Assay; Biomarkers; Copepoda; Copepoda - drug effects; Copepoda - growth & development; Copepods; Crustacea; Ecosystem; ecotoxicology; Ecotoxicology, biological effects of pollution; Endocrine disruption; endocrine-disrupting chemicals; Environmental genomics; Environmental Monitoring - methods; Fundamental and applied biological sciences. Psychology; Gene expression; General aspects; genes; Genomics; genotoxicity; Invertebrates; life history; literature reviews; Marine pollution monitoring; pollutants; salinity; Seawater; stress tolerance; temperature; Tigriopus; toxicity testing; Toxicity Tests - methods; Tribolium; ultraviolet radiation; Water Pollutants, Chemical - poisoning; Water Pollutants, Chemical - toxicity; water pollution; Bioassay; Biomarkers; Endocrine disruption; Copepods; Environmental genomics; Gene expression; Tigriopus; Marine pollution monitoring; Ecotoxicology; Genomics; Biological marker; Endocrine disruptor; Crustacea; Marine environment; Aquatic environment; Arthropoda; Copepoda; Models; Water pollution; Invertebrata
• ISSN: 0166-445X; 1879-1514
• DOI: 10.1016/j.aquatox.2007.04.005

There is an increasing body of evidence to support the significant role of invertebrates in assessing impacts of environmental contaminants on marine ecosystems. Therefore, in recent years massive efforts have been directed to identify viable and ecologically relevant invertebrate toxicity testing models. Tigriopus, a harpacticoid copepod has a number of promising characteristics which make it a candidate worth consideration in such efforts. Tigriopus and other copepods are widely distributed and ecologically important organisms. Their position in marine food chains is very prominent, especially with regard to the transfer of energy. Copepods also play an important role in the transportation of aquatic pollutants across the food chains. In recent years there has been a phenomenal increase in the knowledge base of Tigriopus spp., particularly in the areas of their ecology, geophylogeny, genomics and their behavioural, biochemical and molecular responses following exposure to environmental stressors and chemicals. Sequences of a number of important marker genes have been studied in various Tigriopus spp., notably T. californicus and T. japonicus. These genes belong to normal biophysiological functions (e.g. electron transport system enzymes) as well as stress and toxic chemical exposure responses (heat shock protein 20, glutathione reductase, glutathione S-transferase). Recently, 40,740 expressed sequenced tags (ESTs) from T. japonicus, have been sequenced and of them, 5673 ESTs showed significant hits ( E-value, >1.0E−05) to the red flour beetle Tribolium genome database. Metals and organic pollutants such as antifouling agents, pesticides, polycyclic aromatic hydrocarbons (PAH) and polychrlorinated biphenyls (PCB) have shown reproducible biological responses when tested in Tigriopus spp. Promising results have been obtained when Tigriopus was used for assessment of risk associated with exposure to endocrine-disrupting chemicals (EDCs). Application of environmental gene expression techniques has allowed evaluation of transcriptional changes in T. japonicus with the ultimate aim of understanding the mechanisms of action of environmental stressors. Through a better understanding of toxicological mechanisms, ecotoxicologists may use this ecologically relevant species in risk assessment studies in marine systems. The combination of uses as a whole-animal bioassay and gene expression studies indicate that Tigriopus may serve as an excellent tool to evaluate the impacts of marine pollution throughout the coastal region. The purpose of this review is to illustrate the potential of using Tigriopus to fulfill the niche as an important invertebrate marine model organism for ecotoxicology and environmental genomics. In addition, the knowledge gaps and areas for further studies have also been discussed.