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Focal adhesion kinase-related nonkinase inhibits vascular smooth muscle cell invasion by focal adhesion targeting, tyrosine 168 phosphorylation, and competition for p130(Cas) binding.
- Source :
-
Arteriosclerosis, thrombosis, and vascular biology [Arterioscler Thromb Vasc Biol] 2011 Nov; Vol. 31 (11), pp. 2432-40. - Publication Year :
- 2011
-
Abstract
- Objective: Focal adhesion kinase-related nonkinase (FRNK), the C-terminal domain of focal adhesion kinase (FAK), is a tyrosine-phosphorylated, vascular smooth muscle cell (VSMC)-specific inhibitor of cell migration. FRNK inhibits both FAK and proline-rich tyrosine kinase 2 (PYK2) in cultured VSMCs, and both kinases may be involved in VSMC invasion during vascular remodeling.<br />Methods and Results: Adenovirally mediated gene transfer of green fluorescent protein-tagged, wild-type (wt) FRNK into balloon-injured rat carotid arteries confirmed that FRNK overexpression inhibited both FAK and PYK2 phosphorylation and downstream signaling in vivo. To identify which kinase was involved in regulating VSMC invasion, adenovirally mediated expression of specific short hairpin RNAs was used to knock down FAK versus PYK2 in cultured VSMCs, but only FAK short hairpin RNA was effective in reducing VSMC invasion. The role of FRNK tyrosine phosphorylation was then examined using adenoviruses expressing nonphosphorylatable (Tyr168Phe-, Tyr232Phe-, and Tyr168,232Phe-) green fluorescent protein-FRNK mutants. wtFRNK and all FRNK mutants localized to FAs, but only Tyr168 phosphorylation was required for FRNK to inhibit invasion. Preventing Tyr168 phosphorylation also increased FRNK-paxillin interaction, as determined by coimmunoprecipitation, total internal reflection fluorescence microscopy, and fluorescence recovery after photobleaching. Furthermore, wtFRNK competed with FAK for binding to p130(Cas) (a critically important regulator of cell migration) and prevented its phosphorylation. However, Tyr168Phe-FRNK was unable to bind p130(Cas).<br />Conclusion: We propose a 3-stage mechanism for FRNK inhibition: focal adhesion targeting, Tyr168 phosphorylation, and competition with FAK for p130 binding and phosphorylation, which are all required for FRNK to inhibit VSMC invasion.
- Subjects :
- Adenoviridae genetics
Animals
Carotid Arteries metabolism
Carotid Arteries pathology
Carotid Artery Injuries etiology
Carotid Artery Injuries metabolism
Carotid Artery Injuries pathology
Catheterization adverse effects
Cells, Cultured
Focal Adhesion Kinase 2 genetics
Focal Adhesion Protein-Tyrosine Kinases genetics
Green Fluorescent Proteins genetics
Green Fluorescent Proteins metabolism
Models, Animal
Phosphorylation physiology
Protein Binding physiology
RNA, Small Interfering pharmacology
Rats
Cell Movement physiology
Crk-Associated Substrate Protein metabolism
Focal Adhesion Kinase 2 metabolism
Focal Adhesion Protein-Tyrosine Kinases metabolism
Muscle, Smooth, Vascular metabolism
Muscle, Smooth, Vascular pathology
Protein-Tyrosine Kinases metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1524-4636
- Volume :
- 31
- Issue :
- 11
- Database :
- MEDLINE
- Journal :
- Arteriosclerosis, thrombosis, and vascular biology
- Publication Type :
- Academic Journal
- Accession number :
- 21852560
- Full Text :
- https://doi.org/10.1161/ATVBAHA.111.235549