Electromechanical Properties and Deformation of Biomembranes

生物膜的机电特性和变形

基本信息

批准号：
1748049
负责人：
Petia Vlahovska
金额：
$ 22.4万
依托单位：
Northwestern University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-06-01 至 2020-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1748049&HistoricalAwards=false
关键词：
Electromechanical Properties Deformation Biomembranes

项目摘要

The cells of mammals, birds and reptiles have as their outer edge a thin layer, a cell membrane, that is composed of fatty molecules (lipids). The inside of the cell has a different concentration of charged molecules from the outside of the cell, resulting in an electric field across the membrane that changes its mechanical properties. The mechanical properties of the cell membrane have a profound effect upon how the cell functions. The research will determine by experiment how the mechanical properties of a cell membrane change as the result of exposure to electrical fields. The results of the experiments will be modeled using the engineering methods of 'shell theory' which can model the effects of the curvature of a thin material on its mechanical properties.An electric potential difference across the plasma membrane is common to all living cells and is essential to physiological functions such as generation of action potentials for cell-to-cell communication. While the basics of cell electrical activity are well established (e.g. the Hodgkin-Huxley model of the action potential), the coupling between voltage and membrane deformation has received limited attention. To fill this void, a combined theoretical and experimental study of biomimetic membranes in externally applied electric fields will be studied. Specifically, the research seeks to determine the relation between membrane voltage, membrane properties such as bending rigidity, tension, and spontaneous curvature, and membrane shape. The project integrates theory and experiment to analyze both the small thermally-driven bilayer undulations and the large buckling-like deformations in an applied electric field. The transformative impact of the project lies in its pioneering research of the dynamic coupling between shape and voltage of biomembranes; our findings will uncover new physics relevant to a broad range of physiological processes involving excitable cells.

哺乳动物，鸟类和爬行动物的细胞具有外缘的外缘，薄层，一个由脂肪分子（脂质）组成的细胞膜。细胞的内部与细胞外部具有不同浓度的电荷分子，从而导致整个膜的电场改变其机械性能。细胞膜的机械性能对细胞的功能具有深远的影响。该研究将通过实验确定细胞膜的机械性能如何随着电场暴露而变化。实验的结果将使用“壳理论”的工程方法建模，该方法可以模拟薄材料对机械性能的曲率的影响。质膜上的电势差对于所有生物细胞都是常见的，对于生理功能，例如生理功能，例如生成细胞对细胞对电细胞通信的产生。虽然细胞电活动的基础知识已得到充分确定（例如，动作电位的霍奇金 - 赫克斯利模型），但电压和膜变形之间的耦合受到了有限的关注。为了填补这一空白，将研究对外部电场中仿生膜的理论和实验研究。具体而言，该研究旨在确定膜电压，膜特性（例如弯曲刚度，张力和自发曲率和膜形状）之间的关系。该项目集成了理论和实验，以分析施加的电场中小型热驱动双层的起伏和较大的屈曲样变形。该项目的变革性影响在于其对生物膜形状和电压之间动态耦合的开创性研究。我们的发现将发现与涉及可激发细胞的广泛生理过程有关的新物理学。