Journal
PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY
Volume 466, Issue 5, Pages 987-1001Publisher
SPRINGER HEIDELBERG
DOI: 10.1007/s00424-013-1361-6
Keywords
Stromal interaction molecule 1 (STIM1); Sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 1a (SERCA1a); Skeletal muscle; Excitation-contraction coupling (ECC); Dihydropyridine receptor (DHPR); Store-operated Ca2+ entry (SOCE)
Categories
Funding
- Basic Science Research Program [2012-0007701]
- Mid-career Researcher Program through NRF - MEST [2012-0005435]
Ask authors/readers for more resources
Stromal interaction molecule 1 (STIM1) mediates Ca2+ movements from the extracellular space to the cytosol through a store-operated Ca2+ entry (SOCE) mechanism in various cells including skeletal muscle cells. In the present study, to reveal the unidentified functional role of the STIM1 C terminus from 449 to 671 amino acids in skeletal muscle, binding assays and quadrupole time-of-flight mass spectrometry were used to identify proteins binding in this region along with proteins that mediate skeletal muscle contraction and relaxation. STIM1 binds to sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 1a (SERCA1a) via this region (called STIM1-SBR). The binding was confirmed in endogenous full-length STIM1 in rabbit skeletal muscle and mouse primary skeletal myotubes via co-immunoprecipitation assay and immunocytochemistry. STIM1 knockdown in mouse primary skeletal myotubes decreased Ca2+ uptake from the cytosol to the sarcoplasmic reticulum (SR) through SERCA1a only at micromolar cytosolic Ca2+ concentrations, suggesting that STIM1 could be required for the full activity of SERCA1a possibly during the relaxation of skeletal muscle. Various Ca2+ imaging experiments using myotubes expressing STIM1-SBR suggest that STIM1 is involved in intracellular Ca2+ distributions between the SR and the cytosol via regulating SERCA1a activity without affecting SOCE. Therefore, in skeletal muscle, STIM1 could play an important role in regulating Ca2+ movements between the SR and the cytosol.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available