Related Experiment Video
Updated: Apr 26, 2026
10:08
Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
11.4K
Three dimensional (temperature-tension-composition) phase map of mixed DOPC-DPPC vesicles: Two solid phases and a
1Department of Physics, University of Massachusetts, Amherst, MA 01003, USA.
Biochimica Et Biophysica Acta
|July 28, 2014
Summary
This study maps phospholipid membrane phase behavior, revealing how membrane tension influences fluid-solid coexistence and domain types in DOPC:DPPC mixtures. Understanding these lipid phases is crucial for cell function.
Area of Science:
- Biophysics
- Materials Science
- Physical Chemistry
Background:
- Phospholipid membranes are vital for cell function.
- Previous studies mapped membrane phase behavior in temperature-composition space.
- Membrane tension's role in phase behavior was less understood.
Purpose of the Study:
- To investigate the thermodynamic impact of membrane tension on phase behavior in multicomponent phospholipid membranes.
- To construct a 3D phase map incorporating composition, temperature, and tension.
- To characterize the different types of solid domains formed under varying tension.
Main Methods:
- Utilized model mixed 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) membranes.
- Examined giant unilamellar vesicles (GUVs) under varying tension, temperature, and composition.
- Analyzed domain morphology (hexagonal patches, stripes) and areal densities.
Main Results:
- Developed a 3D composition-temperature-tension phase map.
- Identified two distinct solid DPPC-rich domains: tracer-excluding hexagonal patches (Pβ') and tracer-selective stripes (Lβ').
- Demonstrated tension's influence on fluid-solid coexistence and domain formation, including triple-point-like phenomena.
Conclusions:
- Membrane tension significantly alters phospholipid membrane phase behavior and domain characteristics.
- The identified solid phases (Pβ' and Lβ') and their coexistence boundaries are sensitive to tension.
- This work provides a comprehensive phase map crucial for understanding membrane physics and cellular processes.
Keywords:
CoexistenceEquilibriumMembrane tensionPhospholipid phase diagramPhospholipid phase separationSolid domain shapeMore Related Videos
Related Concept Videos
01:28Phase Diagrams of Ternary Systems
153
Consider a ternary system, which is composed of three components: water (W), ethanoic acid (E), and trichloromethane (T). Here, Ethanoic acid (E) is fully miscible with both water (W) and trichloromethane (T), meaning it can mix entirely with either of them. However, water and trichloromethane have partial miscibility, meaning they can only mix to a certain extent, beyond which two separate phases will form.The phase diagram of a ternary system is represented as an equilateral triangle, where...
153
01:24Phase Diagram
222
A phase diagram is a graphical representation of the physical states of a substance under different conditions of temperature and pressure. It shows the boundaries between solid, liquid, and gas phases and the conditions at which these phases coexist in equilibrium. An area in a phase diagram represents a single phase, whereas lines or phase boundaries represent the equilibrium between two phases.In the phase diagram of water, the boundary line between the solid and liquid states illustrates...
222
01:19Phase Diagram
5.9K
The phase of a given substance depends on the pressure and temperature. Thus, plots of pressure versus temperature showing the phase in each region provide considerable insights into the thermal properties of substances. Such plots are known as phase diagrams. For instance, in the phase diagram for water (Figure 1), the solid curve boundaries between the phases indicate phase transitions (i.e., temperatures and pressures at which the phases coexist).
5.9K
02:39Phase Diagrams
45.5K
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
45.5K
01:32Pinching-off of Coated Vesicles
3.1K
Vesicle budding is orchestrated by distinct cytosolic proteins such as adaptor proteins, coat proteins, and GTPases. To initiate vesicle budding, membrane-bending proteins containing crescent-shaped BAR domains bind to the lipid heads in the bilayer and distort the membrane to form a protein-coated vesicle bud. Adaptors proteins such as AP2 for clathrin-coated vesicles can nucleate on the deformed membrane. Finally, coat proteins such as clathrin or COPI and COPII assemble into a coat forming...
3.1K
00:59COP Coated Vesicles
12.6K
Membrane-enclosed structures called vesicles transport proteins and lipids across the cell. The vesicles derive their cargo from the plasma membrane, Golgi, ER, or endosome. Coated vesicles are spherical, protein-coated carriers with a 50–100 nm diameter that mediate bidirectional transport between the ER and the Golgi. The distribution of proteins between the ER and Golgi complex is dynamic and is maintained by different coated vesicles. Their formation is driven by the assembly of...
12.6K