Stefano Varrella

Stefano Varrella

Stazione Zoologica Anton Dohrn, Italy

Title: Molecular response to toxic diatom-derived aldehydes in the sea urchin Paracentrotus lividus


Stefano Varrella was awarded a master's degree with Honors in Biology from “Federico II” University of Naples in 2012. His undergraduate studies focused on relevance of arginine in DNA oxidative stress induced by copper-H1 histone complexes. In 2013, He enrolled the Open University Ph.D. program at SZN and He is currently working on response to environmental stress in reproduction and embryonic development in sea urchin Paracentrotus lividus. He is trying to understand the cellular mechanisms, mainly by molecular point of view, underlying the stress response of diatom-derived products.


Diatoms are dominant photosynthetic organisms in the world’s oceans and are considered essential in the transfer of energy through the marine food web. These unicellular algae produce secondary metabolites such as polyunsaturated aldehydes and other products deriving from the oxidation of fatty acids, collectively termed oxylipins. In recent years diatom-derived polyunsaturated aldehydes (PUAs) are reported as having a negative influence on the reproductive success of planktonic copepods and benthic invertebrates. In this study we evaluated the effects of two PUAs, heptadienal and octadienal, which have never been tested before from the molecular point of view, using as a model organism the sea urchin Paracentrotus lividus, in comparison with the PUA decadienal, the most studied aldehyde until now. To achieve this goal we followed the expression levels by Real Time qPCR of thirty one genes, having a key role in a broad range of functional responses, such as stress, development, differentiation, skeletogenesis and detoxification processes. Strong differences occurred, suggesting that these stress conditions may alter gene expression and development. These results may be useful to understand how gene expression may be used as an early indicator of stressful conditions in the marine environment. More in general, these studies are fundamental to understand how marine organisms try to defend themselves from environmental toxicants, affording protection by an integrated network of genes.

Speaker Presentations

Speaker PDFs

Speaker PPTs

Download PPT