The effects of formins on the conformation of subdomain 1 in actin filaments

Zoltán Ujfalusi, Szilvia Barkó, G. Hild, M. Nyitrai

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

In this study we investigated the effects of formins on the conformation of actin filaments by using the method of fluorescence quenching. Actin was labelled with IAEDANS at Cys374 and the quencher was acrylamide. The results showed that formin binding induced structural changes in the subdomain 1 of actin protomers which were reflected by greater quenching constants (KSV). Simultaneously the fraction of the fluorophore population accessible for the quencher (α) decreased. These observations suggest that the conformational distribution characteristic for the actin protomers became broader after the binding of formins, for which the structural framework was provided by a more flexible protein matrix in the microenvironment of the label. The effects of formins depended on the formin:actin molar ratio, and also on the ionic strength of the medium. These observations are in agreement with previous results and underline the importance of the intramolecular conformational changes induced by formins in the structure of actin filaments.

Original languageEnglish
Pages (from-to)7-11
Number of pages5
JournalJournal of Photochemistry and Photobiology, B: Biology
Volume98
Issue number1
DOIs
Publication statusPublished - Jan 21 2010

Fingerprint

Actin Cytoskeleton
Actins
filaments
quenching
Protein Subunits
proteins
fluorescence
Acrylamide
matrices
Osmolar Concentration
Fluorescence
Population
Proteins

Keywords

  • Actin
  • fluorescence quenching
  • fluorescence spectroscopy
  • Formin
  • Protein conformation

ASJC Scopus subject areas

  • Radiation
  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology
  • Biophysics

Cite this

The effects of formins on the conformation of subdomain 1 in actin filaments. / Ujfalusi, Zoltán; Barkó, Szilvia; Hild, G.; Nyitrai, M.

In: Journal of Photochemistry and Photobiology, B: Biology, Vol. 98, No. 1, 21.01.2010, p. 7-11.

Research output: Contribution to journalArticle

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