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Self-segregation of myelin membrane lipids in model membranes.

ABSTRACT: Rapid conduction of nerve impulses requires coating of axons by myelin sheaths, which are multilamellar, lipid-rich membranes produced by oligodendrocytes in the central nervous system. To act as an insulator, myelin has to form a stable and firm membrane structure. In this study, we have analyzed the biophysical properties of myelin membranes prepared from wild-type mice and from mouse mutants that are unable to form stable myelin. Using C-Laurdan and fluorescence correlation spectroscopy, we find that lipids are tightly organized and highly ordered in myelin isolated from wild-type mice, but not from shiverer and ceramide synthase 2 null mice. Furthermore, only myelin lipids from wild-type mice laterally segregate into physically distinct lipid phases in giant unilamellar vesicles in a process that requires very long chain glycosphingolipids. Taken together, our findings suggest that oligodendrocytes exploit the potential of lipids to self-segregate to generate a highly ordered membrane for electrical insulation of axons.

SUBMITTER: Yurlova L

PROVIDER: S-EPMC3297774 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Self-segregation of myelin membrane lipids in model membranes.

Yurlova Larisa L Kahya Nicoletta N Aggarwal Shweta S Kaiser Hermann-Josef HJ Chiantia Salvatore S Bakhti Mostafa M Pewzner-Jung Yael Y Ben-David Oshrit O Futerman Anthony H AH Brügger Britta B Simons Mikael M

Biophysical journal 20111201 11

Rapid conduction of nerve impulses requires coating of axons by myelin sheaths, which are multilamellar, lipid-rich membranes produced by oligodendrocytes in the central nervous system. To act as an insulator, myelin has to form a stable and firm membrane structure. In this study, we have analyzed the biophysical properties of myelin membranes prepared from wild-type mice and from mouse mutants that are unable to form stable myelin. Using C-Laurdan and fluorescence correlation spectroscopy, we f ...[more]

PMID: 22261060

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Self-segregation of myelin membrane lipids in model membranes.

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Self-segregation of myelin membrane lipids in model membranes.

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