28.11.2024
Doctoral thesis on the impact of keratins on energy metabolism in the colonic epithelium
M.Sc. Joel Nyström’s doctoral thesis in Cell Biology will be put forth for public defence at The Faculty of Science and Engineering at Åbo Akademi University.
The thesis is entitled Keratin Filaments as Regulators of Intracellular Organization and Metabolism in Colonocytes.
The public defence of the doctoral thesis takes place on Thursday 5 December 2024 at 1PM in Auditorium XXII, Agora, Vesilinnantie 3, Turku. You can also follow the defence online. Professor Rudolf Leube, RWTH Aachen University, Germany, will serve as opponent and Professor John Eriksson, Åbo Akademi University, as custos.
Summary
The innermost layer of the colon wall consists of a single layer of epithelial cells. These cells form an important and protective barrier between the intestinal contents and underlying tissues. Balanced energy metabolism is of importance for epithelial cell function and, consequently, for colonic health. It is relevant to understand epithelial cell function, especially as intestinal diseases, including inflammatory bowel diseases (IBD) and colon cancer, are becoming more common.
Keratins are cytoskeletal proteins that form dynamic filamentous networks in epithelial cells. They provide the cells with mechanical stability, protect against various types of stress and regulate several cellular processes. Keratins play an important role in colonic health, as the loss of keratin 8 in mice leads to intestinal inflammation resembling ulcerative colitis. However, the molecular basis of how keratins regulate colonic function is incompletely understood.
The thesis shows that keratins support the uptake of microbially-produced butyrate, the major energy source of colonic epithelial cells. Keratins also help maintain energy production in mitochondria, the power plants of the cell. The impact of keratins on energy metabolism is likely of importance for colonic health, as maintenance of epithelial cell function requires significant amounts of energy. The thesis also shows that keratins contribute to intracellular organization in colonic epithelial cells by stabilizing mitochondria and regulating their morphology and function. Further, keratins maintain nuclear envelope and lamina composition and, through this, the integrity of the colonic epithelial cell nucleus. Altogether, the thesis provides new knowledge on how keratins contribute to maintaining colonic epithelial health.
Joel Nyström can be reached by phone 050 576 6091 or email joel.nystrom@abo.fi.
The doctoral thesis can be read online through the Doria publication archive.
Click here for a press photo of the doctoral student.
Instructions for following the doctoral defence remotely:
To follow the defence, you need the Zoom software or the Google Chrome browser. You do not need to create a Zoom account to follow the defence. If you install the application, you participate by clicking on the meeting link, after which you should allow the link to open in the Zoom app.