Incorporating Born solvation energy into the three-dimensional Poisson-Nernst-Planck model to study ion selectivity in KcsA K+ channels
文献类型：期刊论文
| 作者 | Liu, Xuejiao; Lu, Benzhuo1
|
| 刊名 | PHYSICAL REVIEW E
 |
| 出版日期 | 2017-12-26 |
| 卷号 | 96期号:6页码:10 |
| ISSN号 | 2470-0045 |
| DOI | 10.1103/PhysRevE.96.062416 |
| 英文摘要 | Potassium channels are much more permeable to potassium than sodium ions, although potassium ions are larger and both carry the same positive charge. This puzzle cannot be solved based on the traditional Poisson-Nernst-Planck (PNP) theory of electrodiffusion because the PNP model treats all ions as point charges, does not incorporate ion size information, and therefore cannot discriminate potassium from sodium ions. The PNP model can qualitatively capture some macroscopic properties of certain channel systems such as current-voltage characteristics, conductance rectification, and inverse membrane potential. However, the traditional PNP model is a continuum mean-field model and has no or underestimates the discrete ion effects, in particular the ion solvation or self-energy (which can be described by Born model). It is known that the dehydration effect (closely related to ion size) is crucial to selective permeation in potassium channels. Therefore, we incorporated Born solvation energy into the PNP model to account for ion hydration and dehydration effects when passing through inhomogeneous dielectric channel environments. A variational approach was adopted to derive a Born-energy-modified PNP (BPNP) model. The model was applied to study a cylindrical nanopore and a realistic KcsA channel, and three-dimensional finite element simulations were performed. The BPNP model can distinguish different ion species by ion radius and predict selectivity for K+ over Na+ in KcsA channels. Furthermore, ion current rectification in the KcsA channel was observed by both the PNP and BPNP models. The I-V curve of the BPNP model for the KcsA channel indicated an inward rectifier effect for K+ (rectification ratio of similar to 3/2) but indicated an outward rectifier effect for Na+ (rectification ratio of similar to 1/6). |
| 资助项目 | National Key Research and Development Program of China[2016YFB0201304] ; Science Challenge Project[TZ2016003] ; China NSF (NSFC)[21573274] ; China NSF (NSFC)[91530102] |
| WOS研究方向 | Physics |
| 语种 | 英语 |
| WOS记录号 | WOS:000418660600018 |
| 出版者 | AMER PHYSICAL SOC |
| 源URL | [http://ir.amss.ac.cn/handle/2S8OKBNM/29284]  |
| 专题 | 计算数学与科学工程计算研究所 |
| 通讯作者 | Lu, Benzhuo |
| 作者单位 | 1.Chinese Acad Sci, Natl Ctr Math, State Key Lab Sci & Engn Comp, Beijing 100190, Peoples R China 2.Chinese Acad Sci, Interdisciplinary Sci Acad Math & Syst Sci, Beijing 100190, Peoples R China 3.Univ Chinese Acad Sci, Sch Math Sci, Beijing 100049, Peoples R China |
| 推荐引用方式 GB/T 7714 | Liu, Xuejiao,Lu, Benzhuo. Incorporating Born solvation energy into the three-dimensional Poisson-Nernst-Planck model to study ion selectivity in KcsA K+ channels[J]. PHYSICAL REVIEW E,2017,96(6):10. |
| APA | Liu, Xuejiao,&Lu, Benzhuo.(2017).Incorporating Born solvation energy into the three-dimensional Poisson-Nernst-Planck model to study ion selectivity in KcsA K+ channels.PHYSICAL REVIEW E,96(6),10. |
| MLA | Liu, Xuejiao,et al."Incorporating Born solvation energy into the three-dimensional Poisson-Nernst-Planck model to study ion selectivity in KcsA K+ channels".PHYSICAL REVIEW E 96.6(2017):10. |
入库方式： OAI收割
来源：数学与系统科学研究院
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