| Abstract |
Mitochondria’s most important function is the oxidative phosphorylation (OXPHOS). They also participate in other functions such as cell death, signalling, synthesis of amino acid, haem, nucleotides and lipids, ion homeostasis, cell motility and proliferation. Hence, mutations in mtDNA have been associated with severe human disorders. These diseases are quite common and can be severe, eventually leading to death. At the moment, mitochondrial diseases cannot be cured. They only can be prevented with mitochondrial replacement therapy (MRT). However, regarding MRT, questions have been raised about the potentially harmful genetic effects of combining the recipient's nuclear genome with the donor's mitochondrial genome. These questions need more research with an experimental system model that will be closer to mammals, but will be much easier to handle. Previous researches have mainly been done in invertebrates such as Drosophila or vertebrates such as mice. Zebrafish (Danio rerio) is a particularly suitable candidate for such an experimental system model because of its easy maintenance and continuous, and almost infinite, supply of eggs. This thesis contains the first steps in using zebrafish as an experimental model for studying mito-nuclear interactions. We examined which strains and species are suitable for the future study of mito-nuclear interactions and heteroplasmy in chimeric fish through DNA sequencing. Genetic distances showed that the genetically more distant strains are AB and SJD (0,75%) and the genetically closest species are D. rerio's AB and D. nigrofasciatus (6,43%). Therefore, after selection through genetic distances, the experiments for measurement of life history traits such as critical swimming speed, heart rate, total length-at-hatch, mortality, hatching rate and growth rate were performed through a series of replicated trials with D. rerio's AB and SJD strains and their hybrid. Through these experiments we characterized the paternal strains and their hybrids for "default" history traits. The species D. nigrofasciatus was not well studied, mostly due to difficulties in its reproduction, which could be solved in the future by in vitro fertilization.
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Consequences of mito-nuclear interactions in life history traits of zebrafish
