Studies

The sequestration of damaged mitochondria within double-membrane structures termed autophagosomes is a key step of PINK1/Parkin mitophagy. The ATG4 family of proteases are thought to regulate autophagosome formation exclusively by processing the ubiquitin-like ATG8 family (LC3/GABARAPs). We discover that human ATG4s promote autophagosome formation independently of their protease activity and of ATG8 family processing. ATG4 proximity networks reveal a role for ATG4s and their proximity partners, ...

Autophagy allows the degradation of cytosolic endogenous and exogenous material in the lysosome. Substrates are engulfed by double-membrane vesicles, coined autophagosomes, which subsequently fuse with lysosomes. Depending on the involvement of specific receptor proteins, autophagy occurs in a selective or nonselective manner. While this process is well understood at the level of bulky cargo such as mitochondria and bacteria, we know very little about individual proteins and protein complexes ...

The ascorbate peroxidase APEX2 is commonly used to study the neighborhood of a protein of interest by proximity-dependent biotinylation. Here, we describe a protocol for sample processing compatible with immunoblotting and mass spectrometry that is suitable to specifically map the content of autophagosomes and potentially other transient vesicles without the need of subcellular fractionation. By combining live-cell biotinylation with proteinase K digestion of cell homogenates, proteins enriched ...

Macroautophagy can regulate cell signalling and tumorigenesis via elusive molecular mechanisms. We establish a RAS mutant cancer cell model where the autophagy gene ATG5 is dispensable in A549 cells in vitro, yet promotes tumorigenesis in mice. ATG5 represses transcriptional activation by the TGFβ-SMAD gene regulatory pathway. However, autophagy does not terminate cytosolic signal transduction by TGFβ. Instead, we use proteomics to identify selective degradation of the signalling scaffold TRAF3. ...

Lewy body (LB) pathology and loss of dopaminergic neurons are imprints of Parkinson’s disease (PD). LBs are mainly comprised of alpha-Synuclein (Dijkstra et al., 2014). Strolling detection of LBs in brain regions contribute to progressive construct of PD pathology to which molecular mechanisms are not clear (H. Braak & Del Tredici, 2017). Two key facets of LB formation are protein aggregation via misfolding and transmission of misfoldled proteins to various brain regions, eventually causing ...

Cell transplantation is a promising approach for the reconstruction of neuronal circuits after brain damage. Transplanted neurons integrate with remarkable specificity into circuitries of the mouse cerebral cortex affected by neuronal ablation. However, it remains unclear how neurons perform in a local environment undergoing reactive gliosis, inflammation, macrophage infiltration, and scar formation, as in traumatic brain injury (TBI). To elucidate this, we transplanted cells from the embryonic ...