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Rab7b regulates dendritic cell migration by linking lysosomes to the actomyosin cytoskeleton
Katharina Vestre1, Irene Persiconi1, Marita Borg Distefano1
1Department of Biosciences, Centre for Immune Regulation, University of Oslo, 0316 Oslo, Norway.
Journal of Cell Science
|September 8, 2021
Summary
Rab7b links lysosomes to the cell
Area of Science:
- Cell Biology
- Immunology
- Biochemistry
Background:
- Lysosomal signaling, involving Ca2+ release, activates myosin II for immune cell migration.
- The physical connection between the actomyosin cytoskeleton and lysosomes remains unclear.
- Rab7b, a GTPase, interacts with myosin II and is involved in lysosome-TGN transport.
Purpose of the Study:
- To elucidate the mechanism by which lysosomes associate with the actomyosin cytoskeleton.
- To investigate the role of Rab7b in dendritic cell (DC) migration.
- To identify the molecular link controlling lysosome-cytoskeleton interactions during cell migration.
Main Methods:
- Investigated Rab7b's role in DC migration in various environments.
- Assessed myosin II light chain phosphorylation and TFEB activation in Rab7b-deficient cells.
- Examined the interaction between Rab7b and the lysosomal Ca2+ channel TRPML1.
Main Results:
- Rab7b deficiency impaired DC migration, reduced myosin II activation, and decreased TFEB activity.
- Rab7b was found to interact with the TRPML1 channel on lysosomes.
- This interaction facilitates localized myosin II activation at the cell rear.
Conclusions:
- Rab7b acts as the crucial physical link between lysosomes and the actomyosin cytoskeleton.
- This Rab7b-mediated connection enables lysosomal signaling to control immune cell migration.
- The findings provide a novel mechanism for regulating immune cell movement.
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