Subcellular targeting of oxidants during endothelial cell migration
Ru Feng Wu1, You Cheng Xu, Zhenyi Ma
1University of Texas Southwestern, Dallas, TX 75390, USA.
The Journal of Cell Biology
|December 7, 2005
Summary
Endogenous oxidants are crucial for endothelial cell migration. This study reveals that TRAF4 localizes NADPH oxidase within focal complexes, enabling oxidative modification essential for cell movement and membrane ruffling.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- Endogenous oxidants play a role in endothelial cell migration.
- Precise subcellular localization of signaling proteins is critical for spatial control of cellular processes.
Purpose of the Study:
- To investigate the subcellular localization and function of NADPH oxidase components in endothelial cell migration.
- To elucidate the role of TRAF4 and its interaction with focal adhesion proteins in regulating cell motility.
Main Methods:
- Immunofluorescence microscopy to visualize protein localization.
- Knockdown experiments using siRNA to assess protein function.
- Biochemical assays to study protein-protein interactions and enzyme activity.
Main Results:
- p47(phox) and TRAF4 were found in focal complex-like structures in motile endothelial cells.
- TRAF4 associated with Hic-5, and their disruption blocked cell migration.
- Active TRAF4 activated NADPH oxidase, leading to oxidative modification of PTP-PEST and Rac1 activation, promoting membrane ruffling.
Conclusions:
- TRAF4 acts as a scaffold, targeting NADPH oxidase to focal complexes for oxidative signaling during endothelial cell migration.
- This localization is critical for regulating cell motility and membrane dynamics.
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