Troponin replacement in permeabilized cardiac muscle Reversible extraction of troponin I by incubation with vanadate

John D. Strauss, Claudia Zeugner, Jennifer E. Van Eyk, Christel Bletz, Monika Troschka, J. Caspar Rüegg

Research output: Contribution to journalArticlepeer-review

Abstract

Calcium-dependent regulation of tension and ATPase activity in permeabilized porcine ventricular muscle was lost after incubation with 10 mM vanadate. After transfer from vanadate to a vanadate-free, low-Ca2+ solution (pCa > 8), the permeabilized muscle produced 84.8% ± 20.1% (± S.D., n=98) of the isometric force elicited by high Ca22+ (pCa ∼4.5 prior to incubation with vanadate. Transfer back to a high Ca2+ solution elicited no additional force (83.2% ± 18.7% of control force). SDS-PAGE and immunoblot analysis of fibers and solutions demonstrated substantial extraction (>90%) of Troponin I (TnI). Calcium dependence was restored after incubation with solutions containing either whole cardiac troponin or a combination of TnI and troponin C subunits. This reversible extraction of troponin directly demonstrates the role of TnI in the regulation of striated muscle contractility and permits specific substitution of the native TnI with exogenously supplied protein.

Original languageEnglish (US)
Pages (from-to)229-234
Number of pages6
JournalFEBS Letters
Volume310
Issue number3
DOIs
StatePublished - Oct 5 1992

Keywords

  • Contractility
  • Muscle regulation
  • Troponin
  • Troponin I
  • Vanadate

ASJC Scopus subject areas

  • Biophysics
  • Structural Biology
  • Biochemistry
  • Molecular Biology
  • Genetics
  • Cell Biology

Fingerprint Dive into the research topics of 'Troponin replacement in permeabilized cardiac muscle Reversible extraction of troponin I by incubation with vanadate'. Together they form a unique fingerprint.

Cite this