ジャーナル: Cell Res / 年: 2016 タイトル: The Central domain of RyR1 is the transducer for long-range allosteric gating of channel opening. 著者: Xiao-Chen Bai / Zhen Yan / Jianping Wu / Zhangqiang Li / Nieng Yan / 要旨: The ryanodine receptors (RyRs) are intracellular calcium channels responsible for rapid release of Ca(2+) from the sarcoplasmic/endoplasmic reticulum (SR/ER) to the cytoplasm, which is essential for ...The ryanodine receptors (RyRs) are intracellular calcium channels responsible for rapid release of Ca(2+) from the sarcoplasmic/endoplasmic reticulum (SR/ER) to the cytoplasm, which is essential for the excitation-contraction (E-C) coupling of cardiac and skeletal muscles. The near-atomic resolution structure of closed RyR1 revealed the molecular details of this colossal channel, while the long-range allosteric gating mechanism awaits elucidation. Here, we report the cryo-EM structures of rabbit RyR1 in three closed conformations at about 4 Å resolution and an open state at 5.7 Å. Comparison of the closed RyR1 structures shows a breathing motion of the cytoplasmic platform, while the channel domain and its contiguous Central domain remain nearly unchanged. Comparison of the open and closed structures shows a dilation of the S6 tetrahelical bundle at the cytoplasmic gate that leads to channel opening. During the pore opening, the cytoplasmic "O-ring" motif of the channel domain and the U-motif of the Central domain exhibit coupled motion, while the Central domain undergoes domain-wise displacement. These structural analyses provide important insight into the E-C coupling in skeletal muscles and identify the Central domain as the transducer that couples the conformational changes of the cytoplasmic platform to the gating of the central pore.
pH: 7.4 詳細: 20 mM MOPS-Na, pH 7.4, 250 mM NaCl, 2 mM DTT, 0.5% CHAPS (w/v) (Sigma-Aldrich) and protease inhibitor cocktail including 2 mM PMSF, 2.6 ug/ml aprotinin, 1.4 ug/ml pepstatin, and 10 ug/ml ...詳細: 20 mM MOPS-Na, pH 7.4, 250 mM NaCl, 2 mM DTT, 0.5% CHAPS (w/v) (Sigma-Aldrich) and protease inhibitor cocktail including 2 mM PMSF, 2.6 ug/ml aprotinin, 1.4 ug/ml pepstatin, and 10 ug/ml leupeptin (Amresco),50 uM CaCl2 and 10 uM PCB95
試料
濃度: 0.066 mg/ml / 包埋: NO / シャドウイング: NO / 染色: NO / 凍結: YES