Cytosolic lipids are surrounded by a phospholipid monolayer and associating proteins that influence lipid droplet growth and degradation. We aim to study specific protein and vesicular trafficking processes that are required for lipid droplet turnover.
We have previously shown that the GTPase ARFRP1 modifies lipid droplet formation by two mechanisms inhibiting lipolysis and regulating lipid droplet fusion (Fig. 1). We therefore hypothesize that ARFRP1 regulates the organization of membrane-associated multidomain scaffolding proteins required for lipid droplet turnover.Â We will focus (1) on scaffolds assembled at the Golgi in response to ARFRP1 action (like golgin proteins), which participate in lipid droplet formation, and (2) will study the role of ARFRP1 for the localization of lipid droplet coating proteins (PAT proteins) in respect to the regulation of lipolysis.Â With cell and animal models lacking the ARFRP1 we will perform biochemical and cell biological studies including several microscopic techniques, pulldown and co-immunoprecipiÂtation experiments in order to understand how membrane scaffolds at the Golgi contribute to the turnover of lipid droplets. Specifically we will
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