摘要
目的:构建瞬时受体电位M8型(TRPM8)离子通道选择性滤器结构域的三维结构模型。方法:在Rosetta计算结构生物学工具包中,使用基于运动回路闭合算法的从头计算,对TRPM8离子通道选择性滤器结构域进行多轮计算建模。结果:经过9轮计算得到了能量最低且结构收敛的TRPM8通道选择性滤器结构域的三维结构模型,发现D918位点的侧链并不指向离子流过的孔区中心,而Q914、D920和T923位点的侧链指向孔区中心;糖基化位点N934位于孔区外侧,其侧链指向胞外水环境。结论:构建了TRPM8通道选择性滤器结构域的三维结构模型,为理解该通道的离子选择性及相关机制提供了较为可靠的结构信息。
Objective: To construct a three-dimensional structural model for the selectivity filter in the transient receptor pontential melastatin 8(TRPM8) ion channel.Methods: In the Rosetta computational structural biology suite, multiple rounds of de novo modeling with the kinematic loop closure algorithm were performed. Results: After nine rounds of computational modeling, we obtained the models of the selectivity filter within the TRPM8 channel with the lowest energy and high convergence. The model showed that the sidechain of D918 points were away from the central ion permeation pathway, while the sidechains of Q914,D920 and T923 pointed towards it. The glycosylation site N934 was located outside the pore region and its side chain directed to the extracellular water environment. Conclusion: A three-dimensional structural model for the selectivity filter in the TRPM8 ion channel was constructed, which provides reliable structural information for exploring the mechanism of ion selectivity.
引文
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