A transcriptomic evaluation of the P. lividus embryo and immune cells response to various stressors

The Paracentrotus lividus embryos and adult immune cells are increasingly used as a model system in toxicological studies for their response sensitivity to chemical/physical stressors and for the recent availability of a high quality genome sequence. Here, we use an omic approach to evaluate the molecular response of a panel of target genes in P. lividus embryos exposed to a number of stressors, i.e. heavy metals, UVB radiations, pharmaceuticals, biochemical inhibitors, and adult immune cells exposed to nanoparticles. In order to perform in vitro eco-toxicological assays, we utilized the experimental conditions of stressor doses, embryonic developmental stages and exposition time already verified on our previous studies. For each assay, we extracted total RNA from controls and treated samples, in order to apply equal quantity to nCounter NanoString technology. For this omic approach, we had previously made an in silico analysis at the NCBI nucleotide database to select sequences of P. lividus transcripts encoding for regulatory and structural proteins including growth and transcription factors, stress and immune response proteins. Thus we retrieved a panel of 130 sequences, including also three potential reference genes, on which Diatech Labline developed custom made probes to hybridize on total RNA. Our analysis on the resulting digital counts, of each hybridized target, highlighted that the altered expression of some categories of genes in some cases might be associated with specific stressors. This study is a contribution to understand the ecological impact of many stressors and supports the development of new tools for the environmental risk assessment.