Zhao Xiaofei, Ding Wen, Wang Hongguang, Wang Yize, Liu Yanjiang, Li Yongdong, Liu Chunliang
Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
ACS Omega. 2024 Feb 12;9(8):9702-9713. doi: 10.1021/acsomega.3c09801. eCollection 2024 Feb 27.
Potassium ion channels are the structural basis for excitation transmission, heartbeat, and other biological processes. The selectivity filter is a critical structural component of potassium ion channels, whose structure is crucial to realizing their function. As biomolecules vibrate and rotate at frequencies in the terahertz band, potassium ion channels are sensitive to terahertz waves. Therefore, it is worthwhile to investigate how the terahertz wave influences the selectivity filter of the potassium channels. In this study, we investigate the structure of the selectivity filter of Kv1.2 potassium ion channels using molecular dynamics simulations. The effect of an electric field on the channel has been examined at four different resonant frequencies of the carbonyl group in SF: 36.75 37.06, 37.68, and 38.2 THz. As indicated by the results, 376GLY appears to be the critical residue in the selectivity filter of the Kv1.2 channel. Its dihedral angle torsion is detrimental to the channel structural stability and the transmembrane movement of potassium ions. 36.75 THz is the resonance frequency of the carbonyl group of 376GLY. Among all four frequencies explored, the applied terahertz electric field of this frequency has the most significant impact on the channel structure, negatively impacting the channel stability and reducing the ion permeability by 20.2% compared to the absence of fields. In this study, we simulate that terahertz waves in the mid-infrared frequency region can significantly alter the structure and function of potassium ion channels and that the effects of terahertz waves differ greatly based on frequency.
钾离子通道是兴奋传递、心跳及其他生物过程的结构基础。选择性过滤器是钾离子通道的关键结构组成部分，其结构对于实现通道功能至关重要。由于生物分子在太赫兹频段的频率下振动和旋转，钾离子通道对太赫兹波敏感。因此，研究太赫兹波如何影响钾通道的选择性过滤器是值得的。在本研究中，我们使用分子动力学模拟研究了Kv1.2钾离子通道选择性过滤器的结构。在选择性过滤器（SF）中羰基的四个不同共振频率下研究了电场对通道的影响：36.75、37.06、37.68和38.2太赫兹。结果表明，376GLY似乎是Kv1.2通道选择性过滤器中的关键残基。其二面角扭转不利于通道结构稳定性和钾离子的跨膜移动。36.75太赫兹是376GLY羰基的共振频率。在所有探索的四个频率中，该频率下施加的太赫兹电场对通道结构的影响最为显著，与无电场时相比，对通道稳定性产生负面影响，并使离子通透性降低20.2%。在本研究中，我们模拟了中红外频率区域的太赫兹波可显著改变钾离子通道的结构和功能，且太赫兹波的影响因频率而异。
