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Published on: October 8, 2015
Spatial Mechano-Signaling Regulation of GTPases through Non-Degradative Ubiquitination.
Raj N Sewduth1,2, Paolo Carai3, Tonci Ivanisevic1,2
1VIB-KU Leuven Center for Cancer Biology, VIB, Leuven, 3000, Belgium.
Blood flow shear stress affects endothelial cells. Non-degradative ubiquitination of GTPases, like RAP1, by WWP2 regulates endothelial function and barrier integrity, impacting vascular health.
Area of Science:
- Vascular Biology
- Cellular Mechanotransduction
- Proteomics and Ubiquitinomics
Background:
- Endothelial cells sense blood flow-induced shear stress, crucial for vascular health.
- Understanding endothelial mechano-activation requires spatial proteome characterization.
Purpose of the Study:
- To investigate the role of ubiquitination in endothelial response to shear stress.
- To identify regulators of GTPase ubiquitination in shear-stressed endothelial cells.
Main Methods:
- Integrative ubiquitinome and proteome analysis of shear-stressed endothelial cells.
- Spatial proteomic analysis to map ubiquitination patterns in vivo.
- Biochemical assays to determine the function of WWP2-mediated RAP1 ubiquitination.
Main Results:
- Non-degradative ubiquitination of GTPases is regulated by mechano-signaling.
- WWP2 ligase regulates RAP1 ubiquitination in response to shear stress.
- WWP2-mediated RAP1 ubiquitination at K31 modulates RAP1 complex formation, suppressing ROS and maintaining endothelial barrier integrity.
Conclusions:
- Spatially regulated non-degradative ubiquitination of GTPases is critical for endothelial mechano-activation.
- WWP2-RAP1 pathway is essential for suppressing shear stress-induced ROS and maintaining endothelial barrier function.
- Dysregulation of this pathway contributes to vascular inflammation.
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