Related Experiment Video
Updated: Jul 8, 2026
10:59
Determination of Lipid Raft Partitioning of Fluorescently-tagged Probes in Living Cells by Fluorescence Correlation Spectroscopy (FCS)
Published on: April 6, 2012
Detecting ordered domain formation (lipid rafts) in model membranes using Tempo
1Dept. of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA.
Methods in Molecular Biology (Clifton, N.J.)
|January 25, 2008
Summary
Short-range fluorescence quenching effectively detects lipid domains in model membranes. The nitroxide molecule TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) aids in identifying ordered domains and their thermal stability.
Area of Science:
- Membrane biophysics
- Lipid domain detection
- Fluorescence spectroscopy
Background:
- Coexisting ordered and disordered lipid domains influence membrane properties.
- Short-range fluorescence quenching is a sensitive method for probing membrane heterogeneity.
- Accurate detection of lipid domains is crucial for understanding membrane function.
Purpose of the Study:
- To present TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) as an effective fluorescence quencher for detecting lipid domains.
- To describe protocols for using TEMPO to identify ordered lipid domains.
- To evaluate TEMPO's utility in assessing the thermal stability of ordered domains.
Main Methods:
- Incorporation of a fluorophore and a quencher molecule into model lipid bilayers.
- Utilizing differential partitioning of fluorophore and quencher into ordered and disordered domains.
- Measuring fluorescence intensity changes to infer domain presence and characteristics.
Main Results:
- TEMPO effectively quenches fluorescence, enabling detection of coexisting lipid domains.
- Segregation of fluorophore and quencher leads to enhanced fluorescence intensity in heterogeneous membranes.
- Protocols for TEMPO application in ordered domain detection and thermal stability assessment are established.
Conclusions:
- TEMPO is a valuable tool for studying lipid domain organization in model membranes.
- This fluorescence quenching approach provides insights into membrane phase behavior.
- TEMPO offers advantages and disadvantages compared to nitroxide-labeled lipids for domain analysis.
More Related Videos
Related Concept Videos
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...
01:26Membrane 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...
01:23Membrane 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...
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...
01:19Fluid 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...
01:28Assembly of the Lipid Bilayer in the ER
Biological membranes are more than just a barrier separating cell cytoplasm from the outside environment. They are highly dynamic and help maintain the integrity and physiological stability of the cells as well as membrane-bound organelles. Membranes also play vital roles in cell-to-cell and intracellular communication.
A large chunk of any biological membrane is composed of phospholipids. These lipids have a heterogeneous distribution across different subcellular organelles and even between...
A large chunk of any biological membrane is composed of phospholipids. These lipids have a heterogeneous distribution across different subcellular organelles and even between...