ESR04 - Biomarker integrated analysis of fish stress

Host Institution: UNIPD - Universit√† degli Studi di Padova

Location: Padova (Italy)

Doctoral degree: PhD in Biosciences at the Universit√† degli Studi di Padova

Job description: The project will be carried out both in the field and in the laboratory. Field trials will be carried out on rivers, using specimens of specially sampled resident fish species, as well as individuals bred in captivity and appropriately placed in water basins. Cytological, biochemical and biomolecular analyzes will be carried out in the laboratory aimed at studying the physiological responses to fish stress. The hypothalamic-pituitary-interrenal axis is one of the systems that most actively responds to stress. In fact, the cells of the hypothalamus lead to the release of cortisol, with physiological changes of the target organs, which reinforce the action of the catecholamines. However, cortisol has inhibitory effects on the growth of fish, on their reproductive success and on the immune system, which makes it clear how environmental stress can have negative effects on individuals and natural populations. One of the objectives of the project will be to study the variation kinetics of the cortisol blood levels and to correlate them to various types of anthropic stress. It will be important to evaluate how cortisol production correlates with the expression of other genes, such as those that encode Crh and Otp, which regulate the production of cortisol. Another objective of the project will be to evaluate the kinetics of response to the risk of oxidative stress. Cells have an antioxidant defense system, consisting of enzymatic and non-enzymatic molecules that are able to counteract the formation of reactive oxygen species, highly oxidizing molecules whose formation rate can easily increase under conditions stress, generating irreversible damage to biological macromolecules, leading to cellular modifications which are the cause of a wide variety of pathological conditions. Although the defensive role of the antioxidant system has long been known, its activation is so complex and species-specific that it is essential to study its peculiarities in the widest range of organisms. Hence the interest in studying the gene expression of the protein components of the antioxidant system (such as SOD, CAT, Gpx and Prdx) of freshwater fish, evaluating both the accumulation of mRNAs and proteins. Knowledge of cortisol and antioxidant defense induction networks can have an important application impact, perfecting the use of biomarkers and bioindicator organisms in the evaluation of anthropic stress in the freshwater environment. For this purpose, the study of these physiological responses will be related to the analysis of cell damage parameters such as DNA breaks and apoptotic index.

Workplace: The candidate will join the Research Unit of Environmental Physiology. It offers to its PhD students a biochemistry laboratory, a biomolecular laboratory, other areas dedicated to processing biological material and networked PC stations. Our PhD students have also access to first-class facilities (among those, Next Generation High Throughput DNA Sequencing, Gene Expression Analysis, online access to scientific bibliographic databases and thousands of scientific journals) at the Department of Biology and work within a friendly and strong international research community.

Secondment period (to be confirmed): Expected duration: 4 months; Hosting institutions: CBAR (Consorzio di Bonifica Acque Risorgive - Venezia, Italy), IGB (Leibniz Institute of Freshwater Ecology and Inland Fisheries - Berlin, Germany)

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Candidate requirements:


  • MSc in Life Sciences (Biology, Natural Sciences, Agricultural Sciences, Biotechnology, or related)
  • Applications from candidates not yet graduated by the call deadline (with Diploma foreseen at the latest by the end of July 2020) are accepted

Specific mandatory skills:  

  • Expertise in UV/VIS spectrophotometry technics
  • Expertise in molecular biology technics 

Specific desirable skills: 

  • Experience in field activity
  • Experience in fish dissection 

Specific requirements of the Doctoral School:

A IELTS certificate is not required for admission to the PhD school in Biosciences, but knowledge of the English language will be assessed during the entrance exam (at least level B2)

Mobility rule:

Applicants must not have resided or carried out their main activity (work, studies, etc.) in Italy for more than 12 months in the 3 years immediately before the recruitment date. Compulsory national service, short stays such as holidays, and time spent as part of a procedure for obtaining refugee status under the Geneva Convention are not taken into account.

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Contact person(s): 

Gianfranco Santovito

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Work package