Mathematics of Ions in Protein Channels

蛋白质通道中离子的数学

• 批准号: 6577542
• 负责人: ROBERT S. EISENBERG
• 金额: $ 35.61万
• 依托单位: RUSH UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6577542
• 关键词: biophysics; calcium ion; density; dielectric property; diffusion; electric field; mathematical model; membrane channels; model design /development; potassium ion; protein structure function; sodium ion

DESCRIPTION (provided by applicant): Ion channels are proteins with holes down their middle (some 0.4 - 1 nm in diameter) that control a wide range of biological function and so are studied in thousands of laboratories every day. Ion channels are ideal objects for physical and mathematical investigation because their structure is simple and quite invariant. Ion channels are ideal objects for biological investigation because they control so many cellular functions and are archetypes of an enormous number of proteins, occupying a substantial fraction of the human genome. Ion channels are objects of great clinical importance because they are involved directly in so many diseases. Ion channels can be studied in the physical tradition because ions move by electrodiffusion through a simple invariant structure following well known laws of diffusion in an electric field. Direct simulation of atomic motion in channels is not feasible on the biological time scale of msec if the system is to include well defined concentrations of ions and electrical potentials. The problem is to know what to average and how to average so the function of channels can be understood and controlled. Here we adopt the engineering approach of multiresolution analysis, proposing a mean field theory in the chemical tradition and stochastic theory in the mathematical tradition of stochastic physics. The central issue in both traditions is to extend previous theories of equilibrium systems to allow prediction of the large currents measured in biological channels.

描述（由申请人提供）： 离子通道是一种蛋白质，其中间有孔（直径约0.4 - 1 nm），控制着广泛的生物功能，因此每天都有数千个实验室对其进行研究。离子通道由于结构简单且具有很强的不变性，是物理和数学研究的理想对象。离子通道是生物学研究的理想对象，因为它们控制着如此多的细胞功能，并且是大量蛋白质的原型，占据了人类基因组的很大一部分。离子通道是具有重要临床意义的对象，因为它们直接参与许多疾病。 离子通道可以在物理学传统中进行研究，因为离子在电场中遵循众所周知的扩散定律，通过电扩散通过简单的不变结构移动。直接模拟通道中的原子运动在毫秒的生物时间尺度上是不可行的，如果系统要包括明确定义的离子浓度和电势。问题是要知道平均什么以及如何平均，以便可以理解和控制通道的功能。在这里，我们采用多分辨率分析的工程方法，提出了化学传统中的平均场理论和随机物理数学传统中的随机理论。这两个传统的中心问题是扩展以前的平衡系统理论，以预测生物通道中测量的大电流。