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Author Spotlight: Imaging ATG9A, a Multi-Spanning Membrane Protein
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ATG9B regulates bacterial internalization via actin rearrangement
Junpei Iibushi1, Takashi Nozawa1, Hirotaka Toh1
1Department of Microbiology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku 606-8501, Kyoto, Japan.
Iscience
|May 6, 2024
Summary
Autophagy-related protein ATG9B controls bacterial invasion by regulating actin rearrangement. This study reveals ATG9B
Area of Science:
- Cell Biology
- Microbiology
- Molecular Biology
Background:
- Bacterial pathogens enter host cells via endocytosis, a process involving actin rearrangement.
- The precise molecular mechanisms governing actin dynamics during bacterial invasion remain incompletely understood.
Purpose of the Study:
- To elucidate the role of autophagy-related (ATG) proteins in bacterial internalization.
- To identify novel regulators of actin rearrangement during host-pathogen interactions.
Main Methods:
- Utilized ATG knockout screening and knockdown experiments in HeLa cells.
- Investigated the effects of ATG9B knockdown on actin filament dynamics, including phosphorylation of LIM kinase and cofilin.
- Examined the influence of Unc-51-like autophagy-activating kinase 1 on ATG9B localization and actin remodeling.
Main Results:
- ATG9B was identified as a critical factor for the internalization of various bacteria.
- ATG9B knockdown led to actin filament accumulation and altered phosphorylation of key actin-regulatory proteins.
- Unc-51-like autophagy-activating kinase 1 activity was shown to modulate ATG9B localization and actin remodeling.
Conclusions:
- ATG9B plays a significant role in regulating actin rearrangement for bacterial invasion.
- This research uncovers a novel function for ATG proteins in bacterial infection, distinct from their known roles in autophagy-mediated immunity.
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