Uncoupling Caveolae from Intracellular Signaling In Vivo
Rationale: Caveolin-1 negatively regulates eNOS derived NO production and this has been mapped to several residues on Cav-1 including F92. Herein, we reasoned that endothelial expression of an F92ACav-1 transgene would let us decipher the mechanisms and relationships between caveolae structure and intracellular signaling.
Objective: This study was designed to separate caveolae formation from its downstream signaling effects.
Methods and Results: An endothelial specific doxycycline-regulated mouse model for the expression of Cav 1 F92A was developed. Blood pressure by telemetry and nitric oxide bioavailability by electron paramagnetic resonance and phosphorylation of VASP were determined. Caveolae integrity in the presence of Cav-1-F92A was measured by stabilization of Cav 2, sucrose gradient and electron microscopy. Histological analysis of heart and lung, echocardiography and signaling were performed.
Conclusions: This study shows that mutant Cav-1-F92A forms caveolae structures similar to WT but leads to increases in NO bioavailability in vivo thereby demonstrating that caveolae formation and downstream signaling events occur through independent mechanisms.
- Received October 5, 2015.
- Revision received November 24, 2015.
- Accepted November 24, 2015.