Bilateral project between Croatia and France (Programme "Cogito" Partnership Hubert Curien for 2013/2014)

Bilateral project between the Republic of Croatia and the Republic of North Macedonia

The problem of environmental contamination with pharmaceutical chemicals has been widely recognized over the past 20 years. The current literature is strongly dominated by studies focused on assessing the exposure concentrations in abiotic matrices (e.g. water and sediments) while reports on the pharmaceutical concentrations in aquatic organisms remain comparatively scarce. However, when considering the possible biological effects, the aqueous exposure concentrations are only an indirect measure of potential toxicity, while the key parameter which determines the substance's potential for adverse effects is its internal concentration in the organism. Consequently, this project aims to provide new insights into the bioaccumulation and metabolic behaviour of pharmaceuticals in freshwater organisms, which is essential for an improved risk assessment of these contaminants as well as for their scientifically-sound prioritization. The project plan includes several interconnected phases, from method development and laboratory-controlled exposure experiments to field studies. Highly specific analytical methods for quantitative multiresidue determination of trace levels of selected pharmaceutical compounds in different environmental matrices (biota, water, sediment) will be developed and validated. These methods will be applied in carefully planned models and field experiments focusing on the characterization of the pharmaceutical exposome in freshwater fish. The model bioaccumulation experiments will be performed using zebrafish (Danio rerio) as the target organism while considering different exposure scenarios. The biochemical responses in fish will be followed by measuring the induction of the major cytochrome P450 detoxification enzymes. As its final step, the project includes a ground-truthing study in the Sava River to assess the pharmaceutical exposome's environmental relevance and collect the critical data for prioritization of individual pharmaceutical contaminants.

Adaptations to the ongoing climate change shape geographic and size distributions of fish, possibly driving some species or populations to extinction. This could endanger fisheries and aquaculture as major sources of dietary protein. How fish adapt to a changing climate is therefore critical to scientists and industry, and with extreme climate becoming more common, fast action is needed.

The objective is to relate algal cell response (in terms of surface properties and physiological behaviour) to main abiotic environmental stressors (temperature and salinity) in order to better understand viability and adaptation strategies of algal populations in aquatic systems

Koristeći multidisciplinarni, cjeloviti pristup, BiREADI ima za cilj ispitati utjecaje atmosferskog taloženja (AT) na složene biokemijske odgovore oligotrofnih vodenih sustava; primarno fitoplanktonskih zajednica te, posljedično, i na kemijske promjene u površinskim slojevima, uključujući mikrosloj na granici faza zrak-voda.

Marine finfish aquaculture is an important industry in Croatia with significant growth potential. Since fish are cultured mainly in near-shore cages open to environmental conditions, their growth and well-being, and therefore the aquaculture production, is susceptible to climate change. The purpose of this interdisciplinary project is to contribute to creating opportunities to improve production and reduce the threat posed by climate change that endangers the viability and development of aquaculture.

DNA-protein crosslink (DPC) is a type of DNA lesion where a protein becomes irreversibly covalently bound to DNA upon exposure to endogenous or exogenous crosslink inducers. Endogenous DPC inducers are products of normal cellular metabolism such as reactive oxygen species, aldehydes and DNA helical alterations, while exogenous inducers include UV light, ionizing radiation and various chemicals. DNA-protein crosslinks are common DNA lesions which present a physical blockage to all DNA transactions: replication, transcription, recombination and repair. If not repaired, DPCs cause genomic instability and adverse phenotypes in humans including premature aging, neurodegeneration and cancer. Despite the frequency and severe outcomes of DPCs, DNA-protein crosslink repair (DPCR) has been sparsely studied, mostly because it has not been considered a separate DNA damage repair pathway until recently. In 2014 and 2016, several groups have identified a novel proteases, Wss1 and SPRTN, which initiate the removal of DPCs through the proteolytic digestion of crosslinked proteins. The discovery of proteolysis-coupled DPC repair lead to recognition of the DNA-protein crosslink repair as a separate DNA damage repair pathway. However, we currently do not know how is the pathway orchestrated and which other factors are involved, while almost nothing is known of DPCR mechanism in vivo. Therefore, within this project we aim to unravel the orchestration of the DPCR pathway in vivo using zebrafish (Danio rerio) as a well-characterized vertebrate model. We will use CRISPR/Cas9 gene manipulation tools to knock-out or mutate specific genes in zebrafish which we suspect are involved in the removal of DNA-protein crosslinks. Contribution of each protein (and their combinations) to the DNA-protein crosslink repair will be quantified after DPC isolation from transgenic zebrafish embryos and adults.

Major challenges face the aquatic systems due to different human activities, which may cause substantial damage to the economy of the region (fisheries, tourism). Our common regional challenge is focused on analyzing pressure in aquatic environment and requires transnational action as recognized in EU Biodiversity Strategy 2020.