Our AIM– the basic ecotoxicological research towards understanding of:
● Molecular base and role of critical cellular defense and/or detoxification mechanisms in aquatic organisms;
● Interactions of cellular defense mechanisms with both, classical and emerging environmental contaminants.
The final goal of the basic investigations described above is the evaluation and positioning of the cellular defense mechanisms as important determinants of the ADME Tox characteristics of environmental contaminants. Finally, results of our studies contribute to the improvement and/or development of the early warning molecular biomarkers and high-throughput screening tools for evaluation of both single environmental contaminants and complex environmental samples.
Main research directions
1.Understanding of the ecotoxicological significance of:
a) Efflux transporters: ABC (ATP binding cassette) and MATE (Multidrug and Toxin extrusion) transport proteins
b) Uptake SLC (Solute carriers) transport proteins: SLC21/OATP and SLC21 protein families
c) GST (Glutathione S-transferase) enzymes: phase 2 of cellular ADME (Administration, Distribution, Metabolism, Elimination)
2.Development of the Effects-Directed Analyses (EDA) approach for identification of hazardous chemical contaminants.
Group Marta Popović – DNA damage
Popovic lab webpage available at: https://martafry.wixsite.com/popoviclab
Group leader: Marta Popovic, PhD
Postdoc: Ivan Mihaljevic, PhD
PhD student: Christine Supina, MSc
Project title: Deciphering DNA-Protein Crosslink Repair in vivo using zebrafish modelProject summary
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 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. We will also generate a GFP reporter assay in cell lines and transgenic fish which will enable the quantification of DPCR efficiency in vitro and in vivo.
More information about the project: https://www.irb.hr/eng/Research/Divisions/Division-for-Marine-and-Environmental-Research/Laboratory-for-molecular-ecotoxicology/DNAPRO-Deciphering-DNA-Protein-Crosslink-Repair-in-vivo-using-zebrafish-model