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Updated: Feb 20, 2026

Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement
Published on: July 26, 2017
Calmodulin dissociates the STIM1-Orai1 complex and STIM1 oligomers
Xin Li1, Guangyan Wu1, Yin Yang2
1State Key Laboratory of Medicinal Chemical Biology and College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin, 300071, China.
Abstract:
Store-operated calcium entry (SOCE) is a major pathway for calcium ions influx into cells and has a critical role in various cell functions. Here we demonstrate that calcium-bound calmodulin (Ca2+-CaM) binds to the core region of activated STIM1. This interaction facilitates slow Ca2+-dependent inactivation after Orai1 channel activation by wild-type STIM1 or a constitutively active STIM1 mutant. We define the CaM-binding site in STIM1, which is adjacent to the STIM1-Orai1 coupling region. The binding of Ca2+-CaM to activated STIM1 disrupts the STIM1-Orai1 complex and also disassembles STIM1 oligomer. Based on these results we propose a model for the calcium-bound CaM-regulated deactivation of SOCE.
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