Mechanosensitive tyrosine phosphorylation of paxillin and focal adhesion kinase in tracheal smooth muscle

Dachun Tang, Dolly Mehta, Susan Gunst

Research output: Contribution to journalArticle

134 Citations (Scopus)

Abstract

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 (L(o)) than at shorter muscle lengths of 0.5 or 0.75 L(o). 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.

Original languageEnglish
JournalAmerican Journal of Physiology - Cell Physiology
Volume276
Issue number1 45-1
StatePublished - 1999

Fingerprint

Paxillin
Focal Adhesion Protein-Tyrosine Kinases
Phosphorylation
Smooth Muscle
Tyrosine
Muscle
Muscles
Integrins
Depolarization
Contractile Proteins
Chemical activation
Actin Cytoskeleton
Protein Kinases
Signal transduction
Smooth Muscle Myocytes
Signal Transduction
Actins

Keywords

  • Contractility
  • Cytoskeleton
  • Focal adhesion proteins
  • Length-tension curve
  • Mechanotransduction
  • Signal transduction

ASJC Scopus subject areas

  • Clinical Biochemistry
  • Cell Biology
  • Physiology
  • Physiology (medical)

Cite this

Mechanosensitive tyrosine phosphorylation of paxillin and focal adhesion kinase in tracheal smooth muscle. / Tang, Dachun; Mehta, Dolly; Gunst, Susan.

In: American Journal of Physiology - Cell Physiology, Vol. 276, No. 1 45-1, 1999.

Research output: Contribution to journalArticle

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