This Article Full Text Full Text (PDF) All Versions of this Article: biophysj.105.065409v1 89/3/1692    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hu, X.-F. Articles by Hu, J. Search for Related Content PubMed PubMed Citation Articles by Hu, X.-F. Articles by Hu, J.

Modulation of the Oligomerization of Isolated Ryanodine Receptors by their Functional States

Xiao-Fang Hu ^*, Xin Liang ^*, Ke-Ying Chen ^*, Hong Xie , Yuhong Xu , Pei-Hong Zhu  and Jun Hu ^* 

^* Bio-X Life Science Research Center, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China; School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China; and Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China

Correspondence: Address reprint requests to Prof. Jun Hu, Bio-X Life Science Research Center, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 1954 Hua-Shan Road, Shanghai 200030, China. Tel.: 86-21-640-77360; Fax: 86-21-644-72577; E-mail: jhu{at}sjtu.edu.cn.

The calcium release channels/ryanodine receptors (RyRs) usually form two-dimensional regular lattices in the endoplasmic/sarcoplasmic reticulum membranes. However, the function and modulation of the interaction between neighboring RyRs are still unknown. Here, with an in vitro aqueous system, we demonstrate that the interaction between RyRs isolated from skeletal muscle (RyR1s) is modulated by their functional states by using photon correlation spectroscopy and [³H]ryanodine binding assay. High level of oligomerization is observed for resting closed RyR1s with nanomolar Ca²⁺ in solution. Activation of RyR1s by micromolar Ca²⁺ or/and millimolar AMP leads to the de-oligomerization of RyR1s. The oligomerization of RyR1s remains at high level when RyR1s are stabilized at closed state by Mg²⁺. The modulation of RyR1-RyR1 interaction by the functional state is also observed under near-physiological conditions, suggesting that the interaction between arrayed RyR1s would be dynamically modulated during excitation-contraction coupling. These findings provide exciting new information to understand the function and operating mechanism of RyR arrays.

This article has been cited by other articles:

				X. Liang, X.-F. Hu, and J. Hu Dynamic Interreceptor Coupling: A Novel Working Mechanism of Two-Dimensional Ryanodine Receptor Array Biophys. J., February 15, 2007; 92(4): 1215 - 1223. [Abstract] [Full Text] [PDF]

				H. Xie and P.-H. Zhu Biphasic Modulation of Ryanodine Receptors by Sulfhydryl Oxidation in Rat Ventricular Myocytes Biophys. J., October 15, 2006; 91(8): 2882 - 2891. [Abstract] [Full Text] [PDF]