Comparative analysis of the transcriptome responses of zebrafish embryos after exposure to low concentrations of cadmium, cobalt and copper

Comp Biochem Physiol Part D Genomics Proteomics. 2018 Mar;25:99-108. doi: 10.1016/j.cbd.2017.12.001. Epub 2017 Dec 15.

Abstract

Metal toxicity is a global environmental challenge. Fish are particularly prone to metal exposure, which can be lethal or cause sublethal physiological impairments. The objective of this study was to investigate how adverse effects of chronic exposure to non-toxic levels of essential and non-essential metals in early life stage zebrafish may be explained by changes in the transcriptome. We therefore studied the effects of three different metals at low concentrations in zebrafish embryos by transcriptomics analysis. The study design compared exposure effects caused by different metals at different developmental stages (pre-hatch and post-hatch). Wild-type embryos were exposed to solutions of low concentrations of copper (CuSO4), cadmium (CdCl2) and cobalt (CoSO4) until 96h post-fertilization (hpf) and microarray experiments were carried out to determine transcriptome profiles at 48 and 96hpf. We found that the toxic metal cadmium affected the expression of more genes at 96hpf than 48hpf. The opposite effect was observed for the essential metals cobalt and copper, which also showed enrichment of different GO terms. Genes involved in neuromast and motor neuron development were significantly enriched, agreeing with our previous results showing motor neuron and neuromast damage in the embryos. Our data provide evidence that the response of the transcriptome of fish embryos to metal exposure differs for essential and non-essential metals.

Keywords: Cadmium; Cobalt; Copper; Essential; Metals; Non-essential; Toxicity; Transcriptomics; Zebrafish embryo.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cadmium / administration & dosage
  • Cadmium / toxicity*
  • Cobalt / administration & dosage
  • Cobalt / toxicity*
  • Copper / administration & dosage
  • Copper / toxicity*
  • Dose-Response Relationship, Drug
  • Embryo, Nonmammalian / metabolism
  • Gene Expression Regulation, Developmental / drug effects
  • Real-Time Polymerase Chain Reaction
  • Toxicity Tests
  • Transcriptome*
  • Water Pollutants, Chemical / toxicity
  • Zebrafish / embryology*
  • Zebrafish / genetics
  • Zebrafish Proteins / genetics*

Substances

  • Water Pollutants, Chemical
  • Zebrafish Proteins
  • Cadmium
  • Cobalt
  • Copper