Muscle Research Group, John Curtin School of Medical Research, Australian National University, PO Box 334, Canberra, ACT, 2601, Australia.
Eur Biophys J. 2009 Dec;39(1):27-36. doi: 10.1007/s00249-009-0449-6. Epub 2009 May 12.
This review focuses on molecular interactions between calsequestrin, triadin, junctin and the ryanodine receptor in the lumen of the sarcoplasmic reticulum. These interactions modulate changes in Ca(2+) release in response to changes in the Ca(2+) load within the sarcoplasmic reticulum store in striated muscle and are of fundamental importance to Ca(2+) homeostasis, since massive adaptive changes occur when expression of the proteins is manipulated, while mutations in calsequestrin lead to functional changes which can be fatal. We find that calsequestrin plays a different role in the heart and skeletal muscle, enhancing Ca(2+) release in the heart, but depressing Ca(2+) release in skeletal muscle. We also find that triadin and junctin exert independent influences on the ryanodine receptor in skeletal muscle where triadin alone modifies excitation-contraction coupling, while junctin alone supports functional interactions between calsequestrin and the ryanodine receptor.
本文综述了肌质网腔中肌联蛋白、三联蛋白、连接蛋白和兰尼碱受体之间的分子相互作用。这些相互作用调节了横纹肌肌质网钙库内钙负荷变化时钙释放的变化，对于钙稳态至关重要，因为蛋白质表达受到调控时会发生大量适应性变化，而兰尼碱受体突变会导致功能变化，甚至可能致命。我们发现，在心脏和骨骼肌中，钙结合蛋白发挥不同的作用，增强心脏中的钙释放，但抑制骨骼肌中的钙释放。我们还发现，三联蛋白和连接蛋白对骨骼肌中的兰尼碱受体有独立的影响，其中三联蛋白单独调节兴奋-收缩偶联，而连接蛋白单独支持肌联蛋白和兰尼碱受体之间的功能相互作用。
