17. On the origin of “Rafts”: The plasma membrane as a microemulsion
Abstract
The hypothesis that the plasma membrane is heterogeneous characterized by regions of saturated lipids and cholesterol which float, like rafts, in a sea of unsaturated lipids seems to be widely accepted. There is no agreement, however, on the physical mechanism that gives rise to these inhomogeneities and accounts for their characteristic size, which is on the order of a 100 nm. In this chapter, one model with a clear physical basis is reviewed. In posits that the inhomogeneities are those characteristic of a microemulsion, one brought about by the coupling of fluctuations in the height of the membrane to fluctuations in the membrane composition.
Abstract
The hypothesis that the plasma membrane is heterogeneous characterized by regions of saturated lipids and cholesterol which float, like rafts, in a sea of unsaturated lipids seems to be widely accepted. There is no agreement, however, on the physical mechanism that gives rise to these inhomogeneities and accounts for their characteristic size, which is on the order of a 100 nm. In this chapter, one model with a clear physical basis is reviewed. In posits that the inhomogeneities are those characteristic of a microemulsion, one brought about by the coupling of fluctuations in the height of the membrane to fluctuations in the membrane composition.
Chapters in this book
- Frontmatter I
- Preface V
- Contents IX
- List of contributing authors XIII
-
Part I. Structural and dynamic characterization
- 1. Biophysical perspectives of lipid membranes through the optics of neutron and X-ray scattering 1
- 2. X-ray structure analysis of lipid membrane systems: solid-supported bilayers, bilayer stacks, and vesicles 43
- 3. Structural investigations of membrane-associated proteins by neutron reflectometry 87
- 4. Collective dynamics in model biological membranes measured by neutron spin echo spectroscopy 131
- 5. Spontaneous lipid transfer rate constants 177
- 6. Fundamentals of Nuclear Magnetic Resonance spectroscopy (NMR) and its applications 195
- 7. Collective dynamics in lipid membranes 231
- 8. Mapping protein– and peptide–membrane interactions by atomic force microscopy: strategies and opportunities 269
- 9. Imaging the distributions of lipids and proteins in the plasma membrane with high-resolution secondary ion mass spectrometry 287
-
Part II. Biomimetic, biorelated, or biological systems
- 10. Cholesterol in model membranes 325
- 11. Study of mitochondrial membrane structure and dynamics on the molecular mechanism of mitochondrial membrane processes 365
- 12. Monitoring oxygen-sensitive membranes and vitamin E as an antioxidant 391
- 13. Giant vesicles: A biomimetic tool for assessing membrane material properties and interactions 415
- 14. Formation and properties of asymmetric lipid vesicles prepared using cyclodextrin-catalyzed lipid exchange 441
- 15. Application and characterization of asymmetric-supported membranes 465
- 16. Styrene-maleic acid copolymers: a new tool for membrane biophysics 477
-
Part III. Molecular dynamics – simulation and theory
- 17. On the origin of “Rafts”: The plasma membrane as a microemulsion 499
- 18. Combining experiment and simulation to study complex biomimetic membranes 515
- 19. Simulations of biological membranes with the Martini model 551
- 20. Multiscale modeling of lipid membrane 569
- 21. Molecular dynamics simulation studies of small molecules interacting with cell membranes 603
Chapters in this book
- Frontmatter I
- Preface V
- Contents IX
- List of contributing authors XIII
-
Part I. Structural and dynamic characterization
- 1. Biophysical perspectives of lipid membranes through the optics of neutron and X-ray scattering 1
- 2. X-ray structure analysis of lipid membrane systems: solid-supported bilayers, bilayer stacks, and vesicles 43
- 3. Structural investigations of membrane-associated proteins by neutron reflectometry 87
- 4. Collective dynamics in model biological membranes measured by neutron spin echo spectroscopy 131
- 5. Spontaneous lipid transfer rate constants 177
- 6. Fundamentals of Nuclear Magnetic Resonance spectroscopy (NMR) and its applications 195
- 7. Collective dynamics in lipid membranes 231
- 8. Mapping protein– and peptide–membrane interactions by atomic force microscopy: strategies and opportunities 269
- 9. Imaging the distributions of lipids and proteins in the plasma membrane with high-resolution secondary ion mass spectrometry 287
-
Part II. Biomimetic, biorelated, or biological systems
- 10. Cholesterol in model membranes 325
- 11. Study of mitochondrial membrane structure and dynamics on the molecular mechanism of mitochondrial membrane processes 365
- 12. Monitoring oxygen-sensitive membranes and vitamin E as an antioxidant 391
- 13. Giant vesicles: A biomimetic tool for assessing membrane material properties and interactions 415
- 14. Formation and properties of asymmetric lipid vesicles prepared using cyclodextrin-catalyzed lipid exchange 441
- 15. Application and characterization of asymmetric-supported membranes 465
- 16. Styrene-maleic acid copolymers: a new tool for membrane biophysics 477
-
Part III. Molecular dynamics – simulation and theory
- 17. On the origin of “Rafts”: The plasma membrane as a microemulsion 499
- 18. Combining experiment and simulation to study complex biomimetic membranes 515
- 19. Simulations of biological membranes with the Martini model 551
- 20. Multiscale modeling of lipid membrane 569
- 21. Molecular dynamics simulation studies of small molecules interacting with cell membranes 603
