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Updated: Aug 14, 2026

Measuring Calpain Activity in Fixed and Living Cells by Flow Cytometry
Published on: July 9, 2010
Calcineurin is a calcium ion-dependent, calmodulin-stimulated protein phosphatase
Abstract:
A Ca2+-dependent, calmodulin-stimulated protein phosphatase (EC 3.1.3.16) is known to be associated with calcineurin, a major calmodulin binding protein in brain. The protein phosphatase activity has now been shown to be retained by a substrate affinity column (thiophosphorylated myosin P-light chain Sepharose) in the presence of Ca2+, and to be eluted specifically with EGTA. Calcineurin behaved identically. This establishes that calcineurin is the Ca2+-dependent protein phosphatase, and that interaction of Ca2+ with the B-subunit is essential for substrate binding.
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