大电导钾离子通道(BK)结构与功能的研究进展

Research Progresses of The Structure and Function of The Large Conductance Potassium Channels(BK)

大电导钙离子激活钾通道(BK)是细胞膜上唯一接受细胞内Ca2+和膜电位双重调控的离子通道.最新发表的关于BK通道电镜结构及其胞质功能域的晶体结构的文章,第一次展示了BK通道各亚基的组装,并证实通道各功能域在通道门控机制中存在紧密的相互作用.近年来,针对BK通道的功能调节及其门控动力学模拟的研究取得较多进展,有助于更好地理解BK通道发挥生理功能的门控机制,并揭示BK通道相关疾病的病理生理学基础.

Large conductance Ca2＋ activated potassium channel （BK） is the only ion channel which is regulated by intracellular Ca2＋ and membrane potential in the cell membrane. Recently the structure of BK determined by cryo-electron microscopy （cryo-EM） shed the first light on the assembly of the whole channel, as well as the crystal structure of the cytosolic domain by x-ray single crystal diffraction. In addition, these 3D structures corroborate many close interactions among these domains during channel gating. More recently, great advancements have been made in the research on functional regulation and gating kinetics simulation of BK channels, these contribute to understand the gating mechanism of the BK channel and the pathophysiological basis of BK-related ion channel diseases.