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.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Yurlova L,Kahya N,Aggarwal S,Kaiser HJ,Chiantia S,Bakhti M,Pewzner-Jung Y,Ben-David O,Futerman AH,Brügger B,Simons Mdoi
10.1016/j.bpj.2011.10.026subject
Has Abstractpub_date
2011-12-07 00:00:00pages
2713-20issue
11eissn
0006-3495issn
1542-0086pii
S0006-3495(11)01247-1journal_volume
101pub_type
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