Toward a molecular understanding of the structure-function of ryanodine receptor Ca2+ release channels: perspectives from recombinant expression systems.

Wales Heart Research Institute, Department of Cardiology, College of Medicine, Cardiff University, UK CF14 4XN.
Cell Biochemistry and Biophysics (Impact Factor: 2.38). 02/2005; 42(2):197-222. DOI: 10.1385/CBB:42:2:197
Source: PubMed

ABSTRACT Identification of the genetic basis of human diseases linked to dysfunctional free calcium (Ca2+) signaling has triggered an explosion of interest in the functional characterization of the molecular components regulating intracellular Ca2+ homeostasis. There is a growing appreciation of the central role of intracellular ryanodine-sensitive Ca2+ release channel (RyR) regulation in skeletal and cardiac muscle pathologies, including malignant hyperthermia, heart failure, and sudden cardiac death. The use of cloned RyR isoforms and recombinant expression techniques has greatly facilitated the elucidation of the molecular basis of RyR Ca2+ release functionality. This review will focus on the recombinant techniques used in the functional characterization of recombinant RyR isoforms and the insights that these approaches have yielded in unraveling the mechanistic basis of RyR channel functionality.

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May 28, 2014