Research Group Leonhardt

Self-renewal and pluripotency are key features of embryonic stem cells (ESCs). In vitro, ESCs can be differentiated into a broad range of cell types representative for all three germ layers of the embryo. Moreover, during differentiation ESCs undergo developmental changes and processes similar to those seen in the inner cell mass during early embryonic development. We have established different methods for spontanous as well as directed differentiation of ESCs that allow us to study epigenetic mechanisms during early development. more

Scientific progress is often limited by the technologies available to researchers. We are constantly aiming to develop new methods and techniques to open new experimental possibilities. more

Until recently, light microscopy was limited by the classical resolution limit. We are using 3D structural illumination microscopy (3D-SIM) to bypass this limit and to study cellular structures well below this limit. more

Microscopic analysis of fluorescently tagged proteins in living cells provide valuable information on the dynamics and functional interactions of proteins in living cells. In addition to the localization of the protein, manipulations of the steady state by bleaching or microirradiation combined with mutational analysis reveal the dynamics of proteins that can be compared to mutated proteins or other cell lines.
We are routinely using the techniques FRAP, FLIP, FRET and Microirradiation in combination with kinetic modeling. These data enables us to dissect complex interactions. more

Epigenetic gene regulation requires the concerted action of a multitude of cis- and trans-acting factors. Regulatory networks of proteins are responsible for the interpretation and setting of epigenetic marks. Hence, it is of critical importance to unravel these networks in order to understand how epigenetic mechanisms function. Using state of the art biochemical approaches we aim to characterize and identify novel protein-protein as well as functional interactions. more

While many cell biological questions can be addressed by analyzing the behavior of populations, it often results in the underestimation of more subtle effects occurring only in subpopulation. In these cases single cell analysis is necessary. Flow cytometry allows analysis of a large number of cells at a single particle level. We apply this technology to study differentiation of embryonic stem cells using flow cytometry to monitor the expression of lineage specific markers. Moreover, we use fluorescence activated cell sorting (FACS) to generate stable transgenic cell lines and isolate specific cell types from tissue samples. more