Deciphering ryanodine receptor array operation in cardiac myocytes
نویسندگان
چکیده
Elemental calcium signals from RYR arrays operating in cardiac myocytes have been extensively characterized with ever-improving optical methods and other innovative techniques. However, the exact nature of elemental calcium signals in terms of RYR gating in situ remains an enigma. Here, we synthesize insights gleaned from recent developments in single-channel resolution of cardiac RYR organization and in visualization of calcium release events that are much smaller than calcium sparks. This synthesis leads to the proposal of a conceptual framework that promises to unify diverse observations in sparkology.
منابع مشابه
The quantal nature of Ca2+ sparks and in situ operation of the ryanodine receptor array in cardiac cells.
Intracellular Ca(2+) release in many types of cells is mediated by ryanodine receptor Ca(2+) release channels (RyRCs) that are assembled into two-dimensional paracrystalline arrays in the endoplasmic/sarcoplasmic reticulum. However, the in situ operating mechanism of the RyRC array is unknown. Here, we found that the elementary Ca(2+) release events, Ca(2+) sparks from individual RyRC arrays in...
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