Influence of Global and Local Membrane Curvature on Mechanosensitive Ion Channels: A Finite Element Approach.
نویسندگان
چکیده
Mechanosensitive (MS) channels are ubiquitous molecular force sensors that respond to a number of different mechanical stimuli including tensile, compressive and shear stress. MS channels are also proposed to be molecular curvature sensors gating in response to bending in their local environment. One of the main mechanisms to functionally study these channels is the patch clamp technique. However, the patch of membrane surveyed using this methodology is far from physiological. Here we use continuum mechanics to probe the question of how curvature, in a standard patch clamp experiment, at different length scales (global and local) affects a model MS channel. Firstly, to increase the accuracy of the Laplace's equation in tension estimation in a patch membrane and to be able to more precisely describe the transient phenomena happening during patch clamping, we propose a modified Laplace's equation. Most importantly, we unambiguously show that the global curvature of a patch, which is visible under the microscope during patch clamp experiments, is of negligible energetic consequence for activation of an MS channel in a model membrane. However, the local curvature (RL < 50) and the direction of bending are able to cause considerable changes in the stress distribution through the thickness of the membrane. Not only does local bending, in the order of physiologically relevant curvatures, cause a substantial change in the pressure profile but it also significantly modifies the stress distribution in response to force application. Understanding these stress variations in regions of high local bending is essential for a complete understanding of the effects of curvature on MS channels.
منابع مشابه
The Combined Effect of Hydrophobic Mismatch and Bilayer Local Bending on the Regulation of Mechanosensitive Ion Channels
The hydrophobic mismatch between the lipid bilayer and integral membrane proteins has well-defined effect on mechanosensitive (MS) ion channels. Also, membrane local bending is suggested to modulate MS channel activity. Although a number of studies have already shown the significance of each individual factor, the combined effect of these physical factors on MS channel activity have not been in...
متن کاملFinite Element Simulation of the Gating Mechanism of Mechanosensitive Ion Channels
In order to eliminate limitations of existing experimental or computational methods (such as patch-clamp technique and molecular dynamics analysis, respectively) a finite element (FE) model for multi length-scale and time-scale investigation of the gating mechanism of mechanosensitive (MS) ion channels has been established. Gating force value (from typical patch clamping values) needed to activ...
متن کاملNumerical solution of unsteady flow on airfoils with vibrating local flexible membrane
Unsteady flow separation on the airfoils with local flexible membrane (LFM) has been investigated in transient and laminar flows by the finite volume element method. A unique feature of the present method compared with the common computational fluid dynamic softwares, especially ANSYS CFX, is the modification using the physical influence scheme in convection fluxes at cell surfaces. In contr...
متن کاملCollective response of self-organized clusters of mechanosensitive channels.
Mechanosensitive channels are ion channels activated by membrane tension. We investigate the influence of the spatial distribution of bacterial mechanosensitive channels on activation (gating). Based on elastic short-range interactions we map this physical process onto an Ising-like model, which enables us to predict the clustering of channels and the effects of clustering on their gating. We c...
متن کاملCollective response of self-organised clusters of mechanosensitive channels
Mechanosensitive channels are ion channels activated by membrane tension. We investigate the influence of bacterial mechanosensitive channels spatial distribution on activation (gating). Based on elastic short-range interactions we map this physical process onto an Ising-like model, which enables us to predict the clustering of channels and the effects of clustering on their gating. We conclude...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Membranes
دوره 6 1 شماره
صفحات -
تاریخ انتشار 2016