On 30 March at 12:15 Antti Matvere will defend his doctoral thesis “Studies on aryl hydrocarbon receptor in murine granulosa cells and human embryonic stem cells” in cell biology.
Prof. Toivo Maimets, University of Tartu
Prof. Arnold Kristjuhan, University of Tartu
Prof. Xavier Coumoul, University Paris Descartes (France)
Aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor. It was initially discovered as a mediator of toxic effects of various environmental pollutants, secreted into the environment as organic waste. These include a wide range of polycyclic and halogenated aryl hydrocarbons, including the highest affinity AHR ligand TCDD. However, research over the past few decades has revealed that AHR has a broad range of functions other than being a sensor to toxic substances. Evidence for this has derived from studies using Ahr knockout animal models as well as the gained knowledge about the vast number of endogenous ligands for AHR. The role of AHR in regulating cellular homeostasis has been shown in various organs and tissues, most prominently in the immune system, liver, lung, fat tissue, brain and cancer. Additionally, AHR has been discovered to be important in reproductive system and in stem cells. Clinical sampling of AHR expression as well as basic research studying the role of AHR has paved way to the prospect of using this protein as a therapeutic target. Today’s research is widely focused on of its potential to serve as a marker in various diseases, but also as being a cellular target in modulation of treatment outcomes. However, the knowledge about the exact functions of this protein is far from complete. In addition, studies have implied AHR to have cell- and tissue-specific functions. The complex nature of this protein has urged to study its expression and functions in different cells. The current thesis focused on characterizing the expression of Ahr gene in murine granulosa cells and human embryonic stem cells. A particular focus was placed on elucidating the regulatory mechanisms controlling Ahr expression. In addition, this thesis aimed to expand the knowledge on the roles of AHR in cellular homeostasis by identification of novel AHR target genes.