Project description:The study of macroalgae capacity to acclimate and recover in environments contaminated with Cu and Cd could prove a promising way to understand the tolerance mechanisms of these seaweeds against different pollutants. This study used as a model organism Gracilaria tenuistipitata (Rhodophyta), a macroalga with economic and ecological importance. The partial transcriptome of G. tenuistipitata was profiled using cDNA microarrays in the sixth day of exposition to EC50 metals. Genes involved in Cu and Cd chronic stress belonging to various functional categories suffered shallow modifications. This possibly indicates that G. tenuistipitata would be in the acclimatization process. In addition, the expression of nine stress genes accompanied by analysis of the photosynthetic rate of seaweed to both metals in three different time frames was analyzed. Genetic variation linked to the mechanism of resistance of the algae, determined from EC50 culture conditions established for two metals, occurred in the early hours of treatment. It was found that G. tenuistipitata was able to accumulate these two metals and to resist and acclimate to the negative effects produced by these elements. The temporal analysis from the nine specific genes showed some specific transcriptional responses of the G. tenuistipitata, exposed to Cu and Cd. Three-condition experiment, control cells cultivated in seawater enriched with von Stosch solution vs. copper and cadmium (indepedent) treated cells. Biological replicates: 4 control, 2 copper treated, 2 cadmium treated. All independently grown and harvested. Four replicates per array.
Project description:The study of macroalgae capacity to acclimate and recover in environments contaminated with Cu and Cd could prove a promising way to understand the tolerance mechanisms of these seaweeds against different pollutants. This study used as a model organism Gracilaria tenuistipitata (Rhodophyta), a macroalga with economic and ecological importance. The partial transcriptome of G. tenuistipitata was profiled using cDNA microarrays in the sixth day of exposition to EC50 metals. Genes involved in Cu and Cd chronic stress belonging to various functional categories suffered shallow modifications. This possibly indicates that G. tenuistipitata would be in the acclimatization process. In addition, the expression of nine stress genes accompanied by analysis of the photosynthetic rate of seaweed to both metals in three different time frames was analyzed. Genetic variation linked to the mechanism of resistance of the algae, determined from EC50 culture conditions established for two metals, occurred in the early hours of treatment. It was found that G. tenuistipitata was able to accumulate these two metals and to resist and acclimate to the negative effects produced by these elements. The temporal analysis from the nine specific genes showed some specific transcriptional responses of the G. tenuistipitata, exposed to Cu and Cd.
Project description:Environmental metals are known to cause harmful effects to fish of which many molecular mechanisms still require elucidation. Particularly concentration dependence of gene expression effects is unclear. Focusing on this matter, zebrafish embryo toxicity tests were used in combination with transcriptomics. Embryos were exposed to three concentrations of copper (CuSO4), cadmium (CdCl2) and cobalt (CoSO4) from just after fertilization until the end of the 48 hpf pre- and 96 hpf post-hatch stage. The RNA was then analyzed on Agilent’s Zebrafish (V3, 4x44K) arrays. Enrichment for GO terms of biological processes illustrated for cadmium that most affected GO terms were represented in all three concentrations, while for cobalt and copper most GO terms were represented in the lowest test concentration only. This suggested a different response to the non-essential cadmium than cobalt and copper. In cobalt and copper treated embryos, many developmental and cellular processes as well as the Wnt and Notch signaling pathways were found significantly enriched. Also, different exposure concentrations affected varied functional networks. In contrast, the largest clusters of enriched GO terms for all three concentrations of cadmium included responses to cadmium ion, metal ion, xenobiotic stimulus, stress and chemicals. However, concentration dependence of mRNA levels was evident for several genes in all metal exposures. Some of these genes may be indicative of the mechanisms of action of the individual metals in zebrafish embryos.