H.M.L.P.B. Herath, Rohini M. de Silva, R.S. Dassanayake, Y.I.N.S. Gunawardene, J.R.P. Jayasingha, A. Schultz, C. Liongue, A.C. Ward, L.O.B. Afonso, K.M. Nalin de Silva
{"title":"Innovative Transgenic Zebrafish Biosensor for Heavy Metal Detection","authors":"H.M.L.P.B. Herath, Rohini M. de Silva, R.S. Dassanayake, Y.I.N.S. Gunawardene, J.R.P. Jayasingha, A. Schultz, C. Liongue, A.C. Ward, L.O.B. Afonso, K.M. Nalin de Silva","doi":"10.1016/j.envpol.2024.125547","DOIUrl":null,"url":null,"abstract":"Heavy metal contamination is an urgent environmental issue that poses a significant threat to human health and the ecosystem. To mitigate the adverse impacts of heavy metal pollution, the aim of this research was to develop genetically engineered zebrafish as biosensors, which offer a promising alternative for detecting heavy metal exposure, specifically Cd<sup>2</sup>⁺ and Zn<sup>2</sup>⁺. A novel heavy metal-sensitive gene construct metallothionine 2 promoter with DsRed reporter gene (<em>mt2</em>-<em>DsRed2</em>) was synthesized and integrated into zebrafish embryos using a Tol2 transposon transposase system with the transgenic zebrafish line subjected to biosensing applications for Cd<sup>2+</sup> and Zn<sup>2+</sup>. The biosensor showed specific responses with linear correlation heavy metal concentration and DsRed fluorescence signal for Cd<sup>2+</sup> and Zn<sup>2+</sup> with (<em>p</em> < 0.01) a minimum detection limit of 4 ppb for each metal ion but not for the non-specific metal ion Ni<sup>2+</sup>, which makes it suitable for laboratory-based heavy metal assessment assays in the low heavy metal concentration ranges of 0-10 ppb. Additionally, the study investigated the toxicity of heavy metals on zebrafish early developmental stages applying a modified version of the OECD Fish Embryo Toxicity (FET-236) test. Accordingly, Cd<sup>2+</sup>, Zn<sup>2+</sup>, and Ni<sup>2+</sup> exhibited no significant toxicity effects on zebrafish embryos within the low dose range of 2-10 ppb confirming the biocompatibility of the transgenic zebrafish biosensor for heavy metal sensing applications. Thus, the developed transgenic zebrafish line can accurately sense heavy metals Cd<sup>2+</sup> and Zn<sup>2+</sup> within the low dose range, making it a promising alternative laboratory assay for environmental monitoring and risk assessment.","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"30 1","pages":""},"PeriodicalIF":7.6000,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Pollution","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1016/j.envpol.2024.125547","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Heavy metal contamination is an urgent environmental issue that poses a significant threat to human health and the ecosystem. To mitigate the adverse impacts of heavy metal pollution, the aim of this research was to develop genetically engineered zebrafish as biosensors, which offer a promising alternative for detecting heavy metal exposure, specifically Cd2⁺ and Zn2⁺. A novel heavy metal-sensitive gene construct metallothionine 2 promoter with DsRed reporter gene (mt2-DsRed2) was synthesized and integrated into zebrafish embryos using a Tol2 transposon transposase system with the transgenic zebrafish line subjected to biosensing applications for Cd2+ and Zn2+. The biosensor showed specific responses with linear correlation heavy metal concentration and DsRed fluorescence signal for Cd2+ and Zn2+ with (p < 0.01) a minimum detection limit of 4 ppb for each metal ion but not for the non-specific metal ion Ni2+, which makes it suitable for laboratory-based heavy metal assessment assays in the low heavy metal concentration ranges of 0-10 ppb. Additionally, the study investigated the toxicity of heavy metals on zebrafish early developmental stages applying a modified version of the OECD Fish Embryo Toxicity (FET-236) test. Accordingly, Cd2+, Zn2+, and Ni2+ exhibited no significant toxicity effects on zebrafish embryos within the low dose range of 2-10 ppb confirming the biocompatibility of the transgenic zebrafish biosensor for heavy metal sensing applications. Thus, the developed transgenic zebrafish line can accurately sense heavy metals Cd2+ and Zn2+ within the low dose range, making it a promising alternative laboratory assay for environmental monitoring and risk assessment.
期刊介绍:
Environmental Pollution is an international peer-reviewed journal that publishes high-quality research papers and review articles covering all aspects of environmental pollution and its impacts on ecosystems and human health.
Subject areas include, but are not limited to:
• Sources and occurrences of pollutants that are clearly defined and measured in environmental compartments, food and food-related items, and human bodies;
• Interlinks between contaminant exposure and biological, ecological, and human health effects, including those of climate change;
• Contaminants of emerging concerns (including but not limited to antibiotic resistant microorganisms or genes, microplastics/nanoplastics, electronic wastes, light, and noise) and/or their biological, ecological, or human health effects;
• Laboratory and field studies on the remediation/mitigation of environmental pollution via new techniques and with clear links to biological, ecological, or human health effects;
• Modeling of pollution processes, patterns, or trends that is of clear environmental and/or human health interest;
• New techniques that measure and examine environmental occurrences, transport, behavior, and effects of pollutants within the environment or the laboratory, provided that they can be clearly used to address problems within regional or global environmental compartments.