An omic approach to dissect molecular responses to different stresses in embryos and adult immune cells of the Paracentrotus lividus complex gene network

An omic approach to dissect molecular responses to different stresses in embryos and adult immune cells of the Paracentrotus lividus complex gene network. Caterina Costa, R. Bonaventura, A. Pinsino, F. Zito, R. Russo Inst. of Biomedicine and Molecular Immunology "A. Monroy", National Research Council, Palermo, Italy. - Paracentrotus lividus is a Mediterranean sea urchin species very sensitive to chemical and physical environmental changes. Recently, it has been proposed as an alternative man-model for toxicological studies by the European Center for Validation of Alternative Methods. Here, we report an extensive transcriptomic analysis on P. lividus embryos and adult immune cells exposed to different stressors in order to assess molecular damages associated to dysregulated expression of target genes. Based on our studies, we performed in vitro eco-toxicological assays by specifically exposing embryos to heavy metals, UVB radiations, pharmaceuticals, biochemical inhibitors and adult immune cells to nanoparticles, respectively. For each assay, we extracted total RNA from control and treated samples. By in silico analyses at the NCBI nucleotide database we selected and retrieved a panel of sequences of P. lividus transcripts encoding for regulatory and structural proteins including growth and transcription factors, stress and immune response proteins. By nCounter NanoString technology, custom made probes were developed on the selected transcripts and hybridized on total RNA. The resulting digital counts of each transcript were compared in the control and treated samples of each assay. Data analyses highlighted the molecular basis of the stressor effects by showing dysregulation at different hierarchical levels of the complex network of interconnected genes, involved in development and immunity signaling pathways. Our investigations contribute to understand the ecological impact of many stressors and support the development of new tools for the environmental risk assessment. This work is dedicated to Dr V. Matranga, who strongly supported this project and did not live enough to see the results. Financed by PO-FESR 2007-2013 - Sicilia - DeCroMed Project - CUP: G93F12000190007. We acknowledge the technical assistance of Mr. Mauro Biondo.