Paracentrotus lividus is a Mediterranean and Eastern Atlantic sea urchin species, very sensitive to chemical and physical environmental changes and widely used in eco-toxicological studies. Here, we applied a high throughput screening approach on P. lividus embryos exposed to UVB radiation (UV), Cadmium Chloride (Cd) and their combination (Cd/UV), to deeply characterize the molecular responses adopted by embryos to cope with these stressors. In vitro eco-toxicological assays were performed by exposing embryos to Cd (10^-4 M) soon after fertilization, to UV (200 and 400 J/m²) at early stage of development, while in co-exposure experiments, Cd-exposed embryos were irradiated with UV at 200 J/m². By NanoString nCounter technology, custom-made probes were developed and hybridized on total RNA extracted from exposed embryos at 51 hours after fertilization. By in silico analyses, we selected and retrieved at the NCBI nucleotide database a panel of P. lividus transcripts encoding for many regulatory and structural proteins that we ranked in categories, i.e., Apoptosis, Biomineralization, Defense, Development, Immunity, Signaling and Transcription Factors. The analysis of 127 transcripts highlighted the dysregulation of many genes, some specifically activated to cope with stress agents, others involved in the complex molecular network of genes that regulate embryo development. We revealed the downregulation of Biomineralization and Development genes and the upregulation of Defensive genes in Cd and Cd/UV embryos. Our approach, using sea urchin embryo as an in vivo model, contributes to advance our knowledge about cellular responses to UV, Cd and their combination.

Paracentrotus lividus是地中海和东大西洋的海胆物种，对化学和物理环境变化非常敏感，并广泛用于生态毒理学研究。在这里，我们对暴露于UVB辐射（UV），氯化镉（Cd）和它们的组合（Cd / UV）的青紫假单胞菌胚胎采用了高通量筛选方法，以深刻表征胚胎为应对这些应激因素而采取的分子反应。 。通过在受精后不久将胚胎暴露于Cd（10 ^-4 M），并在发育的早期暴露于UV（200和400 J / m ²），进行体外生态毒理学测定，而在共同暴露实验中，将Cd暴露以200 J / m ^2的紫外线照射胚胎。通过NanoString nCounter技术，开发了定制的探针，并与受精后51小时从暴露的胚胎中提取的总RNA杂交。通过计算机分析，我们在NCBI核苷酸数据库中选择和检索了一组青紫假单胞菌。编码许多调节和结构蛋白的转录本，我们将其分类为细胞凋亡，生物矿化，防御，发育，免疫，信号传导和转录因子。对127个转录本的分析突显了许多基因的失调，某些基因被专门激活以应对应激因子，而另一些则参与调节胚胎发育的复杂基因网络。我们揭示了Cd和Cd / UV胚胎中生物矿化和发育基因的下调以及防御基因的上调。我们将海胆胚胎用作体内模型的方法有助于增进我们对细胞对UV，Cd及其组合的反应的了解。