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Updated: Sep 27, 2025

Genetic and Biochemical Approaches for In Vivo and In Vitro Assessment of Protein Oligomerization: The Ryanodine Receptor Case Study
Published on: July 27, 2016
Junctophilin-2 allosterically interacts with ryanodine receptor type 2 to regulate calcium release units in mouse
Tianxia Luo1, Ningning Yan, Mengru Xu
1Department of Physiology, School of Medicine, Henan University of Chinese Medicine, Zhengzhou, China.
Abstract:
The interaction between junctophilin-2 (JPH2) and ryanodine receptor type 2 (RyR2) regulated Ca2+ signaling in mouse cardiomyocytes. However, their exact interaction remains unclear. This study elucidates the interaction between JPH2 with RyR2 using co-immunoprecipitation of cardiac sarcoplasmic reticulum vesicles. Additionally, a glutathione S-transferase (GST) pull-down analysis was performed to investigate the physical interaction between RyR2 and JPH2 fragments. JPH2 interacted with RyR2 and the C terminus of the JPH2 protein can pull-down RyR2 receptors. Confocal immunofluorescence imaging indicated that the majority of JPH2 and RyR2 proteins were colocalized near Z-lines in isolated mouse cardiomyocytes. Knockdown of JPH2 reduced the amplitude of Ca2+ transients and disrupted its interaction with RyR2. Therefore, the C-terminus domain of JPH2 is required for interactions with RyR2 in mouse cardiomyocytes, which provides a molecular mechanism for seeking Ca2+-related disease prevention strategies.
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