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Updated: Aug 11, 2026

Measurement of Calcium Fluctuations Within the Sarcoplasmic Reticulum of Cultured Smooth Muscle Cells Using FRET-based Confocal Imaging
Published on: June 20, 2016
Subunits of the calcium ion-pump system of sarcoplasmic reticulum
Abstract:
Sarcoplasmic reticulum membranes with high content of Ca2+ -ATPase (80% of total protein) were dissolved in a non ionic medium and were submitted to isoelectric focusing in polyacrylamide gels. The membrane protein was resolved into six main bands whose isoelectric points range from 6 to 5. The mol. wt. of these peptides is about 100 000 as estimated by second dimension electrophoresis in sodium dodecyl sulfate-polyacrylamide system. The electrophoretic behaviour of the purified ATPase enzyme is similar to that of crude membranes.
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