A TRAF-like E3 ubiquitin ligase TrafE coordinates ESCRT and autophagy in endolysosomal damage response and cell-autonomous immunity to Mycobacterium marinum
- University of Geneva, Switzerland
Abstract
Cells are perpetually challenged by pathogens, protein aggregates or chemicals, that induce plasma membrane or endolysosomal compartments damage. This severe stress is recognised and controlled by the endosomal sorting complex required for transport (ESCRT) and the autophagy machineries, which are recruited to damaged membranes to either repair or to remove membrane remnants. Yet, insight is limited about how damage is sensed and which effectors lead to extensive tagging of the damaged organelles with signals, such as K63-polyubiquitin, required for the recruitment of membrane repair or removal machineries. To explore the key factors responsible for detection and marking of damaged compartments, we use the professional phagocyte Dictyostelium discoideum. We found an evolutionary conserved E3-ligase, TrafE, that is robustly recruited to intracellular compartments disrupted after infection with Mycobacterium marinum or after sterile damage caused by chemical compounds. TrafE acts at the intersection of ESCRT and autophagy pathways and plays a key role in functional recruitment of the ESCRT subunits ALIX, Vps32 and Vps4 to damage sites. Importantly, we show that the absence of TrafE severely compromises the xenophagy restriction of mycobacteria as well as ESCRT-mediated and autophagy-mediated endolysosomal membrane damage repair, resulting in early cell death.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files; Source data files have been provided for Figures 1B, 1C, 1D, 1E, 2A, 2B, 2C, 2D, 2E, 3B, 3C, 3D, 4C, 4E, 5B, 5C, 6D, 6F, 6H, 7B, 7D, 7E, 8A, 8B, 8C, 9B, 9C, 10C, 10D, 11B, 12D, 12E and for Figure 1 - figure supplement 3A, B, C, D, 4A, B, Figure 10 - supplement 1C, 1D, 1E, 1F, 1G. The graph from Figure 1 - figure supplement 2 was generated by analysis of publicly available data https://www.biorxiv.org/content/10.1101/590810v1. The MCV proteomics information was obtained from a publicly available dataset https://www.biorxiv.org/content/10.1101/592717v1.supplementary-material.
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Funding
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (Project grant 310030_188813)
- Lyudmil Raykov
- Manon Mottet
- Jahn Nitschke
- Thierry Soldati
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (Sinergia grant CRSII5_189921)
- Lyudmil Raykov
- Manon Mottet
- Jahn Nitschke
- Thierry Soldati
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Raykov et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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