Fundamental Study of Epithelial-Mesenchymal Transition Induced by Optogenetic Approach

Abstract

In biology, cells are the fundamental units and the essential elements of life. Cells contain to some extent a wealth of information to self-determine their fate, but they also interact with others in a way that impacts their fate. Therefore, an important question is to control the extent of self- vs. mutual fate, i.e. the relative contribution of internal vs. external determinants in the processes by which cells make individual decisions. The epithelial to mesenchymal transition (EMT) is one important process that epithelial cells undergo in some circumstances whereby epithelial cells lose their epithelial features and change to mesenchymal cells. To be specific, the function of EMT destroys cell-cell junction, changes cell morphology and affects motility of cells. Aside from many EMT-inducing factors, a very effective way is to use the transforming growth factor beta (TGF-β). My work is part of a project that aims at the following question : when a cell is triggered undergo EMT, does it respond in a way that depends on other cells, and more specifically, does that response depend on whether or not neighboring cells have also been triggered or not. My work is firstly, to verify the effect of TGF-β with different conditions through immunofluorescence method. Also, I conducted long-term imaging experiment, exploring cellular characteristics and morphological difference under the TGF-β. Our preliminary experiment was to trigger the EMT by uncaging a molecule that is supposed to induce EMT. The most important point to think about is the possibility to make cells damaged owing to UV light. In this project, I aim at observing the effect on epithelial cells under different dose of UV exposure to identify toxicity of UV light. Its toxicity was checked through flow cytometry with apoptosis markers.