Related Experiment Video
Updated: Aug 10, 2026
06:26
Pulling Membrane Nanotubes from Giant Unilamellar Vesicles
Published on: December 7, 2017
Elastic interaction between "hard" or "soft" pointwise inclusions on biological membranes
1Laboratoire de Physico-Chimie Théorique, ESPCI, 10 rue Vauquelin, F-75231 Paris cedex 05, France.
The European Physical Journal. E, Soft Matter
|March 11, 2004
Summary
We calculated elastic interactions between membrane inclusions, finding results depend on inclusion rigidity. Soft inclusions match recent work, while hard inclusions align with established theories.
Area of Science:
- Biophysics
- Soft Matter Physics
- Membrane Biophysics
Background:
- Membrane inclusions interact elastically, influencing membrane properties.
- Previous models often assumed simplified inclusion behaviors (hard or soft).
Purpose of the Study:
- To calculate the induced elastic interaction between pointwise membrane inclusions.
- To analyze the dependence of this interaction on inclusion rigidity.
- To reconcile differing theoretical results for soft and hard inclusions.
Main Methods:
- Theoretical calculation of elastic interaction up to quadratic order with membrane curvature.
- Analysis of limiting cases for inclusion rigidity (Gamma).
Main Results:
- Derived interaction depends on inverse fourth power of separation, with a prefactor influenced by inclusion rigidity (Gamma).
- Large-Gamma (hard inclusions) recovers Goulian et al. results.
- Small-Gamma (soft inclusions) recovers Marchenko and Misbah results, showing consistency.
Conclusions:
- The apparent discrepancy in previous works is resolved by considering the degree of coarse-graining, which determines effective inclusion hardness.
- Conical transmembrane proteins are proposed to be fundamentally hard inclusions.
Related Concept Videos
01:23Membrane Fluidity
Cell membranes are composed of phospholipids, proteins, and carbohydrates loosely attached to one another through chemical interactions. Molecules are generally able to move about in the plane of the membrane, giving the membrane its flexible nature called fluidity. Two other features of the membrane contribute to membrane fluidity: the chemical structure of the phospholipids and the presence of cholesterol in the membrane.Fatty acids tails of phospholipids can be either saturated or...
02:35Noncovalent Attractions in Biomolecules
Noncovalent attractions are associations within and between molecules that influence the shape and structural stability of complexes. These interactions differ from covalent bonding in that they do not involve sharing of electrons.
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
02:04Protein-protein Interfaces
Many proteins form complexes to carry out their functions, making protein-protein interactions (PPIs) essential for an organism's survival. Most PPIs are stabilized by numerous weak noncovalent chemical forces. The physical shape of the interfaces determines the way two proteins interact. Many globular proteins have closely-matching shapes on their surfaces, which form a large number of weak bonds. Additionally, many PPIs occur between two helices or between a surface cleft and a polypeptide...
01:26Membrane Fluidity
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...
01:15Mechanisms of Membrane-bending
The living membranes are flexible due to their fluid mosaic nature; however, their bending into different shapes is an active process regulated by specific lipids and proteins. The membrane bending can be transient as seen in vesicles or stable for a long time as in microvilli. Cells regulate the size, location, and duration of the membrane curvature.
Membrane bending can happen due to intrinsic changes in lipid composition or extrinsic association with different proteins. The proteins involved...
Membrane bending can happen due to intrinsic changes in lipid composition or extrinsic association with different proteins. The proteins involved...
00:59Mechanisms of Membrane Domain Formation
Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with cytoskeletal...
Another mechanism for membrane domain formation involves membrane proteins interacting with cytoskeletal...