Actin as a potential target for decavanadate. | - CCMAR -

Journal Article

TitleActin as a potential target for decavanadate.
Publication TypeJournal Article
AuthorsRamos, S, Moura, JJG, Aureliano, M
Year of Publication2010
JournalJ Inorg Biochem
Volume104
Issue12
Date Published2010 Dec
Pagination1234-9
ISSN1873-3344
KeywordsActins, Adenosine Triphosphate, Animals, Electron Spin Resonance Spectroscopy, Rabbits, Vanadates
Abstract

ATP prevents G-actin cysteine oxidation and vanadyl formation specifically induced by decavanadate, suggesting that the oxometalate-protein interaction is affected by the nucleotide. The ATP exchange rate is increased by 2-fold due to the presence of decavanadate when compared with control actin (3.1×10(-3) s(-1)), and an apparent dissociation constant (k(dapp)) of 227.4±25.7 μM and 112.3±8.7 μM was obtained in absence or presence of 20 μM V(10), respectively. Moreover, concentrations as low as 50 μM of decameric vanadate species (V(10)) increases the relative G-actin intrinsic fluorescence intensity by approximately 80% whereas for a 10-fold concentration of monomeric vanadate (V(1)) no effects were observed. Upon decavanadate titration, it was observed a linear increase in G-actin hydrophobic surface (2.6-fold), while no changes were detected for V(1) (0-200 μM). Taken together, three major ideas arise: i) ATP prevents decavanadate-induced G-actin cysteine oxidation and vanadate reduction; ii) decavanadate promotes actin conformational changes resulting on its inactivation, iii) decavanadate has an effect on actin ATP binding site. Once it is demonstrated that actin is a new potential target for decavanadate, being the ATP binding site a suitable site for decavanadate binding, it is proposed that some of the biological effects of vanadate can be, at least in part, explained by decavanadate interactions with actin.

DOI10.1016/j.jinorgbio.2010.08.001
Sapientia

http://www.ncbi.nlm.nih.gov/pubmed/20807665?dopt=Abstract

Alternate JournalJ. Inorg. Biochem.
PubMed ID20807665
CCMAR Authors