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Updated: Sep 25, 2026

Assessment of Sarcoplasmic Reticulum Calcium Reserve and Intracellular Diastolic Calcium Removal in Isolated Ventricular Cardiomyocytes
11:00

Assessment of Sarcoplasmic Reticulum Calcium Reserve and Intracellular Diastolic Calcium Removal in Isolated Ventricular Cardiomyocytes

Published on: September 18, 2017

Ca2+ -dependent interaction of S100A1 with the sarcoplasmic reticulum Ca2+ -ATPase2a and phospholamban in the human

Roland Kiewitz1, Christian Acklin, Beat W Schäfer

  • 1Department of Pediatrics, Division of Clinical Chemistry and Biochemistry, University of Zürich, Steinwiesstr. 75, CH-8032, Zürich, Switzerland.

Biochemical and Biophysical Research Communications
|June 14, 2003
PubMed

Insights

The S100A1 protein regulates heart contractility. This study identified S100A1

Area of Science:

  • Cardiology
  • Molecular Biology
  • Biochemistry

Background:

  • S100A1 protein is highly expressed in the human heart and regulates contractility.
  • Reduced S100A1 levels are linked to impaired calcium handling in heart failure.

Purpose of the Study:

  • To investigate the S100A1 signaling pathway in the human heart.
  • To identify S100A1 target proteins involved in cardiac function.

Main Methods:

  • S100A1-specific affinity chromatography and immunoprecipitation were used.
  • Confocal laser scanning microscopy and immunoelectron microscopy were employed.

Main Results:

  • A calcium-dependent complex of S100A1 with SERCA2a and PLB was detected in the human myocardium.
  • S100A1, SERCA2a, and PLB co-localize at the sarcoplasmic reticulum (SR) in cardiomyocytes.

Conclusions:

  • S100A1 interacts with SERCA2a and PLB, suggesting a role in calcium regulation.
  • These findings support a regulatory role for S100A1 in the cardiac contraction-relaxation cycle.

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