S100A1 decreases calcium spark frequency and alters their spatial characteristics in permeabilized adult ventricular cardiomyocytes

Völkers, M., Loughrey, C. M., MacQuaide, N., Friedrich, O. and et al. (2007) S100A1 decreases calcium spark frequency and alters their spatial characteristics in permeabilized adult ventricular cardiomyocytes. Cell Calcium, 41 2: 135-143. doi:10.1016/j.ceca.2006.06.001


Author Völkers, M.
Loughrey, C. M.
MacQuaide, N.
Friedrich, O.
et al.
Title S100A1 decreases calcium spark frequency and alters their spatial characteristics in permeabilized adult ventricular cardiomyocytes
Journal name Cell Calcium   Check publisher's open access policy
ISSN 0143-4160
1532-1991
Publication date 2007-02
Sub-type Article (original research)
DOI 10.1016/j.ceca.2006.06.001
Volume 41
Issue 2
Start page 135
End page 143
Total pages 9
Editor Alex Verkhratsky
S. Muallem
Place of publication Edinburgh, U.K.
Publisher Churchill Livingstone
Language eng
Subject 0601 Biochemistry and Cell Biology
0606 Physiology
Formatted abstract
S100A1, a Ca2+-sensor protein of the EF-hand type, exerts positive inotropic effects in the heart via enhanced cardiac ryanodine receptor (RyR2) activity. Here we report that S100A1 protein (0.1 μM) interacts with the RyR2 in resting permeabilized cardiomyocytes at free Ca2+-levels comparable to diastolic Ca2+-concentrations (∼150 nM). Alterations of RyR2 function due to S100A1 binding was assessed via analysis of Ca2+-spark characteristics. Ca2+-spark frequency, amplitude and duration were all reduced upon perfusion with 0.1 μM S100A1 protein by 38%, 14% and 18%, respectively. Most likely, these effects were conveyed through the S100A1 C-terminus (S100A1-ct; amino acids 75-94) as the corresponding S100A1-ct peptide (0.1 μM) inhibited S100A1 protein binding to the RyR2 and similarly attenuated frequency, amplitude and duration of Ca2+-sparks by 52%, 8% and 26%, respectively. Accordingly, the sarcoplasmic reticulum (SR) Ca2+-content was slightly increased but the stoichiometry of other accessory RyR2 modulators (sorcin/FKBP12.6) remained unaltered by S100A1. Hence, we propose S100A1 as a novel inhibitory modulator of RyR2 function at diastolic Ca2+-concentrations in rabbit ventricular cardiomyocytes.
© 2006.
Keyword S100A1
Calcium
Sparks
Ryanodine receptor
Q-Index Code C1

Document type: Journal Article
Sub-type: Article (original research)
Collections: Excellence in Research Australia (ERA) - Collection
School of Biomedical Sciences Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 40 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 44 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Tue, 06 Apr 2010, 15:47:06 EST by June Temby on behalf of Faculty of Science