Master transcription factors (TFs) cooperate with chromatin in regulating genomic activity in animal development and stress response. Local clustering of TFs into dense, sub-micrometer size condensates is emerging as a key feature of transcriptional regulation. This includes intranuclear condensates formed by pioneer TFs during development, transient clusters of RNA Polymerase II complex and nuclear stress bodies formed during a heat shock. Despite the ubiquity of these assemblies, we know little about the biophysical mechanism of their formation or physiological function. The last years have seen the development of new frameworks to study such transient assemblies, including various types of phase transitions and tools to probe and modulate them. However, this work has been limited mainly to cell culture and in vitro experiments that failed to incorporate the vital role of chromatin in organizing gene regulation. I propose a cross-disciplinary strategy consisting of a novel in vitro assays and functional studies in a nematode Caenorhabditis elegans to study the spatial organization of transcription in embryonic development and stress response. The specific aims are: 1. Understand the physiological relevance of transcriptional condensates in animal development and stress response. 2. Determine the molecular composition and regulators of transcriptional condensates. 3. Dissect the mechanism of transcriptional condensate formation using a novel chromatin carpet assay. We will use state-of-the-art microscopy-based tools to investigate the formation and function of nuclear condensates in developing animal embryos and develop innovative assays to probe the condensation of TFs on the surface of purified native chromatin. The obtained results will provide an unprecedented insight into the composition, assembly mechanism, and physiological relevance of biomolecular condensates formed by the transcriptional apparatus during differentiation and stress response.

Non-Alcoholic Fatty Liver Disease (NAFLD), including its more pathologic consequence, non-alcoholic steatohepatitis (NASH), is believed to be the most common chronic liver disease worldwide, affecting between 6 to 37% of the population. NAFLD is a so called ‘silent killer’, as clinical symptoms only surface at late stages of the disease, when it is no longer treatable: untreated, NAFLD/NASH can lead to cirrhosis and hepatocellular carcinoma, culminating in liver failure. Currently the best method of diagnosing and staging the disease is liver biopsy, a costly, invasive and somewhat risky procedure, not to mention unfit for routine assessment. Besides, no therapeutic consensus exists for NAFLD/NASH treatment. mtFOIE GRAS (Foie Gras being French for "fat liver") proposes to address the pressing need for non-invasive, accurate, rapid assessment of NAFLD/NASH stages, before and after intervention, through the development of biomarkers and innovative tools to follow mitochondrial (mt) dysfunction, a central mediator of fatty liver disease pathogenesis. This promising R&D strategy will also bring new knowledge about the disease mechanisms and improved understanding of the pathogenic process and disease drivers. To that end, mtFOIE GRAS envisages a training-through-work plan that brings together an intersectoral, multidisciplinary team of researchers and technicians experts in their fields, from basic to translational research, clinical practice, technology commercialization and public advocacy. Together with several PhD students, the team will share expertises and work synergistically along the value creation chain to address the unmet medical need of more informative NAFLD assessment. In the process, mtFOIE GRAS will endow the involved staff with excellent scientific knowledge and transferable skills while building and strengthening intersectoral cooperation among partners, thus contributing to EU RD&I excellence.