Dynamin-2 controls actin remodeling for efficient complement receptor 3-mediated phagocytosis.
Anna Mularski1, Ryszard Wimmer1, Floriane Arbaretaz1
1Université Paris Cité, CNRS, INSERM, Institut Cochin, Paris, France.
Biology of the Cell
|April 25, 2023
Summary
Dynamin-2 is crucial for phagocytosis, the process where cells engulf particles. This protein regulates actin assembly in the phagocytic cup, ensuring successful complement receptor 3 (CR3)-mediated engulfment.
Area of Science:
- Cell Biology
- Immunology
Background:
- Phagocytosis is a key cellular process for clearing pathogens and debris.
- Complement receptor 3 (CR3) on macrophages mediates the uptake of many particles.
- Understanding actin dynamics during phagocytosis is essential for elucidating CR3-mediated mechanisms.
Purpose of the Study:
- To investigate the role of Dynamin-2 in CR3-mediated phagocytosis.
- To understand the interaction of Dynamin-2 with the actin cytoskeleton during phagosome formation.
Main Methods:
- Recruitment analysis of Dynamin-2 during phagocytosis.
- Inhibition of Dynamin activity to assess its impact on phagocytic cups and F-actin.
Main Results:
- Dynamin-2 is recruited with polymerized actin to the phagocytic cup.
- Dynamin inhibition results in stalled phagocytic cups and reduced F-actin.
- Dynamin-2 plays a role in actin remodeling downstream of integrins.
Conclusions:
- Dynamin-2 is essential for regulating F-actin assembly in the phagocytic cup.
- Dynamin-2 is a key regulator for successful CR3-mediated phagocytosis.
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