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Updated: Jun 20, 2026
07:20
Imaging ATG9A, a Multi-Spanning Membrane Protein
Published on: June 16, 2023
Keeping up with ATG7: conserved functions in Atg8ylation and beyond
Valgerdur J Hjaltalin1, Margret Helga Ogmundsdottir1
1Department of Biomedical Science, Biomedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
Autophagy
|June 19, 2026
Summary
Atg8ylation, a key process in autophagy, is conserved across eukaryotes. This review explores the evolutionary history of ATG7, an enzyme crucial for Atg8ylation and other cellular functions.
Area of Science:
- Cell Biology
- Molecular Biology
- Evolutionary Biology
Background:
- Atg8ylation is a vital process in autophagy, involving the conjugation of Atg8-family proteins to cellular membranes.
- This process is increasingly recognized as a general eukaryotic membrane-tagging system, similar to ubiquitin tagging.
- While canonical autophagy is well-studied, Atg8ylation beyond this context is primarily explored in mammals.
Purpose of the Study:
- To review and organize the functions of ATG7 across different eukaryotic clades.
- To understand the evolutionary history of ATG7's roles, particularly in Atg8ylation and independent functions.
- To highlight conserved and divergent functions of ATG7 throughout eukaryotic evolution.
Main Methods:
- Literature review and comparative analysis of ATG7 functions across eukaryotic clades.
- Focus on Atg8ylation on both double-layered and single-layered membranes.
- Examination of Atg8ylation-independent functions of ATG7.
Main Results:
- Atg8ylation on single-layer membranes is a conserved function of ATG7 across eukaryotes.
- While Atg8ylation-independent functions of ATG7 are well-documented in mammals, their conservation in other eukaryotes is less explored.
- Evidence suggests potential conservation of some Atg8ylation-independent ATG7 functions in non-mammalian eukaryotes.
Conclusions:
- ATG7 plays a conserved role in Atg8ylation across eukaryotes, particularly on single-layer membranes.
- The evolutionary perspective reveals conserved and potentially conserved functions of ATG7 beyond canonical autophagy.
- Further research is needed to fully elucidate the conserved Atg8ylation-independent functions of ATG7 in diverse eukaryotic lineages.
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