Mechanosensitive tyrosine phosphorylation of paxillin and focal adhesion kinase in tracheal smooth muscle
| Autor: | Susan J. Gunst, Dolly Mehta, Dachun Tang |
|---|---|
| Předmět: |
Physiology
macromolecular substances In Vitro Techniques Potassium Chloride Focal adhesion chemistry.chemical_compound Dogs Reference Values Isometric Contraction medicine Animals Phosphorylation Mechanotransduction Paxillin Actin biology Muscle Smooth Tyrosine phosphorylation Cell Biology Protein-Tyrosine Kinases Phosphoproteins Acetylcholine Cell biology Trachea Cytoskeletal Proteins chemistry Focal Adhesion Protein-Tyrosine Kinases biology.protein Tyrosine Mechanosensitive channels medicine.symptom Cell Adhesion Molecules Mechanoreceptors Muscle Contraction Muscle contraction |
| Zdroj: | Europe PubMed Central |
| Popis: | We investigated the role of the integrin-associated proteins focal adhesion kinase (FAK) and paxillin as mediators of mechanosensitive signal transduction in tracheal smooth muscle. In muscle strips contracted isometrically with ACh, we observed higher levels of tyrosine phosphorylation of FAK and paxillin at the optimal muscle length ( Lo) than at shorter muscle lengths of 0.5 or 0.75 Lo. Paxillin phosphorylation was also length sensitive in muscles activated by K+depolarization and adjusted rapidly to changes in muscle length imposed after contractile activation by either ACh or K+depolarization. Ca2+depletion did not affect the length sensitivity of paxillin and FAK phosphorylation in muscles activated with ACh, indicating that the mechanotransduction process can be mediated by a Ca2+-independent pathway. Since Ca2+-depleted muscles do not generate significant active tension, this suggests that the mechanotransduction mechanism is sensitive to muscle length rather than tension. We conclude that FAK and paxillin participate in an integrin-mediated mechanotransduction process in tracheal smooth muscle. We propose that this pathway may initiate alterations in smooth muscle cell structure and contractility via the remodeling of actin filaments and/or via the mechanosensitive regulation of signaling molecules involved in contractile protein activation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|