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Updated: Sep 29, 2025
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Evaluation of LC3-II Release via Extracellular Vesicles in Relation to the Accumulation of Intracellular LC3-positive Vesicles
Published on: October 18, 2024
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LC3B is an RNA-binding protein to trigger rapid mRNA degradation during autophagy
Hyun Jung Hwang1,2, Hongseok Ha1,2, Ban Seok Lee1,2
1Creative Research Initiatives Center for Molecular Biology of Translation, Korea University, Seoul, 02841, Republic of Korea.
Nature Communications
|March 18, 2022
Summary
Microtubule-associated protein 1A/1B-light chain 3B (LC3B) binds mRNA and promotes its degradation, enhancing autophagy. This RNA-binding role is crucial for efficient autophagic pathways.
Area of Science:
- Molecular Biology
- Cell Biology
- Autophagy Research
Background:
- Microtubule-associated protein 1A/1B-light chain 3 (LC3/ATG8) is central to autophagy, the process of degrading cytoplasmic components.
- The specific molecular functions of LC3 in RNA biology remain largely unexplored.
Purpose of the Study:
- To investigate the role of LC3B as an RNA-binding protein.
- To elucidate the mechanisms by which LC3B influences mRNA stability and autophagy.
Main Methods:
- RNA-binding assays to identify mRNA targets of LC3B.
- Transcriptome-wide analysis to profile LC3B-regulated mRNAs.
- Investigation of LC3B's role in mRNA decay pathways, including the CCR4-NOT complex.
Main Results:
- LC3B directly binds to mRNAs, showing a preference for the AAUAAA polyadenylation motif.
- Autophagic activation enhances LC3B-mRNA association, leading to rapid mRNA degradation.
- PRMT1 mRNA, a negative regulator of autophagy, was identified as a major LC3B target, and its degradation facilitates autophagy.
Conclusions:
- LC3B functions as an RNA-binding protein with mRNA decay capabilities.
- LC3B-mediated mRNA degradation is essential for efficient autophagy.
- LC3B plays a novel role in regulating gene expression during the autophagic process.
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