Talin binds to actin and promotes filament nucleation

FEBS Lett. 1991 Jun 24;284(2):187-91. doi: 10.1016/0014-5793(91)80681-r.

Abstract

Platelet talin binds to actin in vitro and hence is an actin binding protein. By four different non-interfering assay conditions (fluorescence, fluorescence recovery after photobleaching, (FRAP), dynamic light scattering and DNase-I inhibition) we show that talin promotes filament nucleation, raises the filament number concentration and increases the net rate of actin polymerization but has no inhibitory effect on filament elongation. Binding of talin to actin occurs at a maximal molar ratio of 1:3 as determined by fluorescencetitration under G-buffer conditions. The overall binding constant was approximately 0.25 microM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism*
  • Blood Platelets / chemistry
  • Blood Proteins / isolation & purification
  • Blood Proteins / metabolism*
  • Blood Proteins / pharmacology
  • Cytoskeletal Proteins / isolation & purification
  • Cytoskeletal Proteins / metabolism*
  • Cytoskeletal Proteins / pharmacology
  • Deoxyribonuclease I / antagonists & inhibitors
  • Light
  • Photochemistry
  • Polymers / metabolism
  • Scattering, Radiation
  • Spectrometry, Fluorescence
  • Talin

Substances

  • Actins
  • Blood Proteins
  • Cytoskeletal Proteins
  • Polymers
  • Talin
  • Deoxyribonuclease I