RésuméDeciphering the role of non-homologous-end joining and homologous recombination during the DNA repair mechanism of the bdelloid rotifer Adineta vaga
Adineta vaga, bdelloid rotifer, is a peculiar micro-organism able to survive in extreme conditions and to reproduce asexually since millions of years. As an illustration of their high capacity of stress tolerance, bdelloid rotifers exhibit a resistance to high doses of ionizing radiation up to 2,000Gy. Such doses of ionizing radiation lead to a high level of DNA double strand break (DSB) that are actively repaired by bdelloid rotifers.
During this master thesis, we tried to decipher the DNA repair mechanisms behind the bdelloid extreme resistance to ionizing radiation and their DNA DSB. Usual repair mechanisms of DSB in metazoans involve either non-homologous end joining (NHEJ) or homologous recombination (HR). Following 800Gy irradiations, variation of gene expression implicated in NHEJ or HR support the, for now hypothetical, presence of those mechanisms. Once the methods perfectly optimized, protein expression and localization analyses will provide further insights on the extraordinary DNA mechanism undergoing in bdelloid rotifers.
The understanding of this mechanism might also give us lead on what strategy asexual organisms developed to evolve and diversify in the absence of a sexual reproduction, which is the gold standard evolutionary choice to create diversity in a population.
|la date de réponse||16 janv. 2020|
|Superviseur||Karine Van Doninck (Promoteur) & Bernard Hallet (Copromoteur)|