Group of the Structure and Function of the Cell Nucleus

Laboratory Structure and Function of the Cell Nucleus is preferentially interested in studies on 3D-nuclear architecture using high-resolution confocal microscopy. Fluorescent techniques such as immunocytochemistry, and DNA/RNA-FISH combined with confocal microscopy are used for analyses of nuclear radial distribution of chromatin structures and nuclear distribution of chromatin associated proteins. We focus on study of nuclear structures that play an important role in RNA processes. We visualize and observe particular chromosome territories, genes, centromeres, telomeres, nuclear bodies, nuclear speckles, and cytoskeleton components in different experimental cellular systems. Another field of our research is study of epigenetic patterns in the cell nucleus and its impact on important processes such as gene transcription. We are concerned in changes in histone code owing to treatment with inhibitors of enzymes that mediate histone modifications, such as methylation and acetylation. These inhibitors are often used in preclinical studies leading to cancer therapy. We investigate nuclear processes also with techniques based on molecular biology or proteomics. We perform e.g. chromatin immunoprecipitation (ChIP-PCR, ChIP-on-chip), RT-PCR, western blots and flow cytometry. Recently, our experiments are strongly headed towards the living cell studies. High resolution confocal microscopy systems and GFP technology enable us to investigate processes in living cells, e.g. during differentiation. In our laboratory we have successfully established FRAP (Fluorescence Recovery after Photobleaching) technique which allows us to study dynamics of nuclear and nucleolar proteins. We are also able to induce DNA double strand breaks (DSBs) using UV laser and then observe DNA repair processes in cell nucleus. Our experiments should explain importance of specific nuclear architecture in regulation of nuclear/cellular processes such transcription, DNA repair and cell differentiation. We would like to contribute to the knowledge on chromatin biology of cancer cells, human embryonic stem cells, iPS cells and tumor cell lines stimulated to various differentiation pathways.