Area of Study
Science and Mathematics
During maturation, oocytes (immature eggs) progress from prophase I to metaphase II of meiosis, and a multitude of other cellular changes occur. β-catenin is a unique protein as it is involved in cell-cell adhesion when it is bound in plasma membrane complexes, and acts as a transcription factor when freed into the cytoplasm and allowed to move into the nucleus. β-catenin has been found to take part in signaling pathways such as the Wnt/β-catenin pathway, which inhibits β-catenin degradation, and subsequently regulates gene transcription. β-catenin has also been found to exist in distinct molecular forms depending on its role, which may limit competition between the roles of adhesion and signaling. I aimed to test the hypothesis that the concentration of β-catenin in the cytoplasm increases in zebrafish oocytes during maturation. By destabilizing the cytoskeleton and freeing β-catenin into the cytoplasm with lactrunculin A, I determined if the overall concentration of β-catenin changes during maturation. Concentration changes were determined through Western blotting, and qualitative analysis was preformed through visualization with confocal microscopy. If β-catenin increases in both cytoplasmic concentration and overall amount after maturation, this would suggest that the increase is due to processes in the cytoplasm, such as a Wnt-like signaling pathway preventing the degradation of β-catenin or the new translation of protein, as opposed to the recruitment of β-catenin from the cell membrane. The results of confocal microscopy suggested that the amount of cytoskeletal β-catenin does not change during maturation, but the results of Western blotting were inconclusive.
Pincus, Nathan, "Determining the Origin of Changing β-catenin Concentrations in Zebrafish Oocytes During Maturation" (2011). Summer Research. 89.
University of Puget Sound