Occurrence of actin-like protein in extracellular matrix vesicles

A. Muhlrad, I. A. Bab, D. Deutsch, J. Sela*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

18 Scopus citations

Abstract

Preliminary indications of the occurrence of actin and myosin in crude matrix vesicle preparations have been reported previously. In the present study extracellular matrix vesicles from rat alveolar bone were isolated. They were further purified by a sucrose density gradient. SDS-polyacrylamide gel electrophoresis of the purified vesicles revealed the presence of a polypeptide with a molecular weight of 43 K daltons and with electrophoretic mobility identical to that of blood platelet actin. The limited proteolysis of both 43 K dalton vesicular polypeptide and actin by Staphylococcus aureus-V8-protease revealed three fragments with identical electrophoretic mobility. In addition, the vesicular preparations inhibited the activity of DNase I, a property typical of actin monomers. Filamentous material extracted from matrix vesicles showed ultrastructural features of F-actin. Reaction of this material with heavy meromyosin resulted in arrowhead formation, which is characteristic of acto-heavy meromyosin. The occurrence of actin in extracellular matrix vesicles may account for their budding from the osteoblastic plasma membrane, their possible motility in the matrix, and maintenance of the spherical shape.

Original languageEnglish
Pages (from-to)376-381
Number of pages6
JournalCalcified Tissue International
Volume34
Issue number1
DOIs
StatePublished - Dec 1982

Keywords

  • Actin
  • Bone
  • Matrix vesicles
  • Rat

Fingerprint

Dive into the research topics of 'Occurrence of actin-like protein in extracellular matrix vesicles'. Together they form a unique fingerprint.

Cite this