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目的：建立和验证电压门控型钾通道的结构模型．方法：（１）从实验和理论研究结果中提取结构约束条件；（２）建立满足这些约束条件的初始结构模型，并进一步用限制性分子力学优化；（３）根据模型能否成功地解释通道功能分子机制和许多实验事实来判断其合理性．结果：（１）建立了一个孔区模型，其中信号序列残基（对应Ｓｈａｋｅｒ４３９－４４６）以非周期性构象嵌入膜中并形成孔区比较窄的部分，而孔区域的其它残基构成孔区外口；（２）通道离子选择性在４４５，４４７位置处分别通过阳离子π轨道作用机理和氧笼机理来实现；（３）ＣＴＸ和ＡｇＴｘ２与孔区的不同结合方式导致了它们通道亲和力的差异；（４）孔区内侧静电势主要为负．结论：构建的模型与从实验结果导出的限制信息是相一致的．
Objective: To establish and verify the structure model of voltage-gated potassium channel. Methods: (1) The structural constraints were extracted from the experimental and theoretical research results. (2) The initial structural model satisfying these constraints was established and further optimized with the restrictive molecular mechanics. (3) According to the model, whether the channel can be successfully explained Functional and molecular mechanisms and many experimental facts to judge its rationality. Results: (1) A well model was established in which the signal sequence residues (corresponding to Shaker 439-446) were embedded in the membrane in a non-periodic conformation and formed a narrower part of the pore and the other residues in the pore region constituted the pore (2) Channel ion selectivity at 445,447 positions were achieved through cation-π orbital mechanism and oxygen cage mechanism, respectively. (3) The different binding modes of CTX and AgTx2 with pore regions resulted in their channel affinity Difference; (4) pore area medial electrostatic potential is mainly negative. Conclusion: The constructed model is consistent with the restriction information derived from the experimental results.