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Degradation of cytosolic components by autophagy is a crucial process for cellular and tissue homeostasis.Over the last decade this research field has tremendously expanded and a lot of effort has been made to dissect the signaling mechanisms that regulate autophagy initiation and to unravel the origin of membranes that contribute to the newly formed, sequestering phagophore.Initially these questions were mainly answered in light of non-selective turnover of cytosol upon nutritional starvation.However, over the last years it has become clear that autophagy also can selectively target cargo, such as protein aggregates (aggrephagy) and diverse organelles (mitochondria, peroxisomes etc).Even though several cargo receptor molecules that allow for a molecular link between selected cargo and the autophagic machinery via direct interaction with LC3 have been identified, very little is known about how selective autophagy is induced (thereby giving rise to LC3 containing phagophores) and how autophagic membranes and cargo are brought into close proximity.We therefore have focused on the selective turnover of puromycin induced protein aggregates in order to understand the early events of phagophore formation and cargo delivery to the autophagic membrane.Capturing these extremely dynamic events requires high spatial-temporal resolution which we obtained by a correlative light and electron microscopy (CLEM) approach.Interestingly, both NBR1 and p62 can be found in such aggregates;however NBR1 has a more dominant role in the formation of these aggregates.We are currently trying to understand whether the formation and turnover of these aggregates is coupled and how the assembly of the autophagic machinery is proceeding in regard to the aggregates.