Related Experiment Video
Updated: May 19, 2026
07:18
Lipid Bilayer Experiments with Contact Bubble Bilayers for Patch-Clampers
Published on: January 16, 2019
Structural interactions between lipids, water and S1-S4 voltage-sensing domains
Dmitriy Krepkiy1, Klaus Gawrisch, Kenton J Swartz
1Molecular Physiology and Biophysics Section, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA. klausg@mail.nih.gov
Journal of Molecular Biology
|August 4, 2012
Summary
Voltage-sensing domains interact extensively with membrane lipids and water. Arginine residues in these domains are hydrated and near lipids, crucial for ion channel function.
Area of Science:
- Structural biology
- Biophysics
- Membrane protein chemistry
Background:
- Membrane proteins are vital for cellular functions, but their structures and lipid interactions remain poorly understood.
- Voltage-activated ion channels' S4 helix is exposed to the membrane, and lipids affect channel activity.
Purpose of the Study:
- Investigate lipid and water interactions with voltage-sensing domains (S1-S4).
- Determine if lipids influence the structure and hydration of S1-S4 domains.
Main Methods:
- Solid-state Nuclear Magnetic Resonance (NMR) spectroscopy.
- Studied interactions of S1-S4 domains with lipids and water.
Main Results:
- S1-S4 domains show extensive lipid interactions and significant hydration within membranes.
- Anionic lipids preferentially interact with S1-S4 domains (lifetimes ≤ 10(-3)s).
- Arginine residues are hydrated and interact with lipid headgroups and acyl chains.
Conclusions:
- Arginine residues in S1-S4 domains are hydrated near the membrane's hydrophobic core.
- These interactions are essential for charge transport and voltage-driven protein movements.
More Related Videos
Related Concept Videos
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...
01:18Membrane Domains
The membrane domains concentrate specific lipids and proteins at one place within the membrane, which helps in cell signaling, adhesion, and other critical cellular processes. These domains can differ in size, composition, function, and lifespan.
Protein Domains
The membrane comprises a group of distinct proteins responsible for carrying out a cell's specific function. For example, the plasma membrane of the human sperm, or a single germ cell, contains a unique set of proteins in the anterior...
Protein Domains
The membrane comprises a group of distinct proteins responsible for carrying out a cell's specific function. For example, the plasma membrane of the human sperm, or a single germ cell, contains a unique set of proteins in the anterior...
01:43SNAREs and Membrane Fusion
Once a transport vesicle has recognized its target organelle, the vesicular membrane needs to fuse with the target membrane to unload the cargo. Transmembrane proteins called SNAREs present on organelle membranes and their vesicles, mediate vesicle fusion.
SNAREs exist in pairs that symmetrically interact and catalyze the fusion of the lipid bilayers in vesicle and target organelle. v-SNARE in the vesicle membrane are single polypeptide chains that bind to a complementary t-SNARE, composed of 2...
SNAREs exist in pairs that symmetrically interact and catalyze the fusion of the lipid bilayers in vesicle and target organelle. v-SNARE in the vesicle membrane are single polypeptide chains that bind to a complementary t-SNARE, composed of 2...
01:35Asymmetric Lipid Bilayer
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
01:19Fluid Mosaic Model
Scientists identified the plasma membrane in the 1890s and its principal chemical components (lipids and proteins) by 1915. The model for plasma membrane structure, proposed in 1935 by Hugh Davson and James Danielli, was the first model to be widely accepted in the scientific community. The model was based on the plasma membrane's "railroad track" appearance in early electron micrographs. Davson and Danielli theorized that the plasma membrane's structure resembled a sandwich with the analogy of...
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...