Mechanisms of Selective Autophagy
Trond Lamark1, Terje Johansen1
1Molecular Cancer Research Group, Department of Medical Biology, University of Tromsø - The Arctic University of Norway, 9037 Tromsø, Norway; email: trond.lamark@uit.no, terje.johansen@uit.no.
Annual Review of Cell and Developmental Biology
|June 21, 2021
Summary
Selective autophagy receptors (SARs) mediate the targeted degradation of cellular components. This review explores how SARs recognize substrates and interact with forming autophagosomes via LIR-ATG8 interactions for efficient cellular cleanup.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Selective autophagy is a crucial cellular process for degrading specific intracellular components.
- This process relies on selective autophagy receptors (SARs) that link cargo to the autophagosome machinery.
- SARs utilize conserved motifs (LIRs/AIMs) to interact with ATG8 family proteins, facilitating cargo sequestration.
Purpose of the Study:
- To review the mechanisms of mammalian selective autophagy.
- To highlight unifying principles in substrate recognition by SARs.
- To elucidate the role of LIR-ATG8 interactions in autophagosome formation on substrates.
Main Methods:
- This is a review article, synthesizing existing research.
- Focuses on mechanistic insights into selective autophagy.
- Integrates findings on substrate recognition, receptor-autophagosome interactions, and component recruitment.
Main Results:
- SARs employ distinct strategies for cargo recognition, which can be ubiquitin-dependent or independent.
- A key interaction involves SARs binding to ATG8 proteins via LIR motifs.
- Efficient autophagosome biogenesis at the substrate site requires recruitment of core autophagy machinery.
Conclusions:
- Selective autophagy utilizes conserved molecular mechanisms for targeted degradation.
- LIR-ATG8 interactions are central to linking cargo to the autophagosome.
- Understanding these principles is key to comprehending cellular homeostasis and disease.
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