Dynamic exchange of myosin molecules between thick filaments. Academic Article uri icon

Overview

abstract

  • To examine thick filament assembly and myosin exchange, a fluorescence energy transfer assay has been established. Assembly-competent myosin molecules labeled with the sulfhydryl-specific fluorochromes 5-(2-[(iodoacetyl)-amino]ethyl)aminonaphthalene-1-sulfonic acids (IAEDANS) or 5-iodoacetamidofluorescein (IAF) were prepared. Using IAEDANS-labeled myosin as fluorescence donor and IAF-labeled myosin as acceptor, thick filament formation was followed by the decrease in donor fluorescence at 0.1 M KCl/10 mM potassium phosphate, pH 6.9. The critical concentration of myosin--i.e., that concentration that remained unassembled at equilibrium with fully formed filaments--was 40 nM. In FET and 125I-labeled myosin incorporation assays, extensive exchange of myosin between thick filaments was observed. The presence of a critical concentration and the measurements of extensive exchange suggest a dynamic equilibrium between fully polymerized myosin and a small pool of soluble myosin.

publication date

  • December 1, 1986

Research

keywords

  • Actin Cytoskeleton
  • Cytoskeleton
  • Myosins

Identity

PubMed Central ID

  • PMC387164

Scopus Document Identifier

  • 0022899348

Digital Object Identifier (DOI)

  • 10.1073/pnas.83.24.9483

PubMed ID

  • 3467317

Additional Document Info

volume

  • 83

issue

  • 24