E-GEOD-50975 - How does exposure of yellow perch (Perca flavescens) to nickel and cadmium affect the transcriptome-results from a 1000 candidate-gene microarray
Released on 19 September 2013, last updated on 3 June 2014
Our main objectives were: 1) to identify transcriptional signatures specific to the exposure to two metals: Ni and Cd; 2) to investigate the mechanisms of toxicity for these two metals; and 3) to develop a predictive tool to identify the sublethal effects of Ni and Cd contaminants in fish sampled from natural environments. The molecular mechanisms underlying nickel (Ni) and cadmium (Cd) toxicity and their specific effects on fish are poorly understood. Documenting gene transcription profiles offers a powerful approach towards identifying the molecular mechanisms affected by these metals and to discover biomarkers of their toxicity. However, confounding environmental factors can complicate the interpretation of the results and the detection of biomarkers for fish captured in their natural environment. In the present study, a 1000 candidate-gene microarray, developed from a previous RNA-seq study on a subset of individual fish from contrasting level of metal contamination, was used to investigate the transcriptional response to metal (Ni and Cd) and non metal (temperature, oxygen, and diet) stressors in yellow perch (Perca flavescens). Specifically, we aimed at 1) identifying transcriptional signatures specific to Ni and Cd exposure, 2) investigating the mechanisms of their toxicity, and 3) developing a predictive tool to identify the sublethal effects of Ni and Cd contaminants in fish sampled from natural environments. A total of 479 genes displayed significantly different transcription levels when temperature varied while 287 and 177 genes were differentially transcribed at different concentrations of Ni and Cd, respectively. These metals were found to mainly affect the transcription level of genes involved in iron metabolism, transcriptional and translational processes, vitamin metabolism, blood coagulation, and calcium transport. In addition, a linear discriminant analysis (LDA) made using gene transcription levels yielded 94% correctly reassigned samples regarding their level of metal contamination, which indicates the potential of the microarray to detect perch response to Cd or Ni effects. Comparison between fish exposed to three temperatures (11, 20, 28°C) using a loop design, comparison between control fish and fich exposed to restrictive diet using a pairwise design, comparison between fish exposed to hypoxia and control fish, comparison between fish exposed to two concentrations of cadmium and control fish using a loop design, and comparison between fish exposed to two concentrations of nickel and control fish using a loop design.
transcription profiling by array
Berenice BOUGAS <email@example.com>, Berenice Bougas, Eric Normandeau, Fabien Pierron, Louis Bernatchez, Patrice Couture, Peter G Campbell