Structure of cholesterol/ceramide monolayer mixtures: implications to the molecular organization of lipid rafts.
The structure of monolayers of cholesterol/ceramide mixtures was investigated using grazing incidence x-ray diffraction, immunofluorescence, and atomic force microscopy techniques. Grazing incidence x-ray diffraction measurements showed the existence of a crystalline mixed phase of the two components within a range of compositions of cholesterol/ceramide between 100:0 and 67:33. The mixed phase coexists with the ceramide crystalline phase in the range of compositions between 50:50 and 30:70; between 30:70 and 0:100 only the highly crystalline phase of ceramide was detected. The latter was determined and modeled. Immunolabeling was performed with an antibody specific to the cholesterol monohydrate crystalline arrangement. The antibody recognizes crystalline cholesterol monolayers, but does not interact with crystalline ceramide. Immunofluorescence and atomic force microscopy data show that in uncompressed ceramide monolayers, the highly crystalline phase coexists with a disordered loosely packed phase. In contrast, no disordered phase coexists with the new crystalline mixed phase. We conclude that the new mixed phase represents a stable homogeneous arrangement of cholesterol with ceramide. As ceramide incorporates the lipid backbone common to all sphingolipids, this arrangement may be relevant to the understanding of the molecular organization of lipid rafts.
Scheffer
Luana
L
Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
Solomonov
Inna
I
Weygand
Markus Jan
MJ
Kjaer
Kristian
K
Leiserowitz
Leslie
L
Addadi
Lia
L
D000388:Air; D001703:Biophysics / Q000379:methods; D002518:Ceramides / Q000737:chemistry*; D002784:Cholesterol / Q000737:chemistry*; D003460:Crystallization; D008055:Lipids / Q000737:chemistry; D021962:Membrane Microdomains / Q000737:chemistry* / Q000378:metabolism; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence; D008956:Models, Chemical; D015233:Models, Statistical; D013499:Surface Properties; D013696:Temperature; D014867:Water; D014961:X-Ray Diffraction
D002518:Ceramides; D008055:Lipids; D014867:Water; D002784:Cholesterol
Biochem Biophys Res Commun. 1997 Nov 7;240(1):1-7
9367871
Proc Natl Acad Sci U S A. 2000 Nov 7;97(23):12422-7
11050164
Biophys J. 2000 Nov;79(5):2616-23
11053134
J Lipid Res. 2003 Apr;44(4):655-67
12562849
Chemistry. 2000 Mar 3;6(5):869-74
10826609
FASEB J. 1996 Oct;10(12):1435-42
8903514
Chem Biol. 1996 Jul;3(7):567-77
8807889
Chem Rev. 2001 Jun;101(6):1659-96
11709995
Biophys J. 2003 Jan;84(1):367-78
12524290
J Struct Biol. 2000 Jul;131(1):38-43
10945968
Biophys J. 2004 Feb;86(2):880-90
14747323
J Lipid Res. 2001 Sep;42(9):1492-500
11518770
Biophys J. 2001 Nov;81(5):2729-36
11606285
J Cell Biol. 2000 Mar 6;148(5):997-1008
10704449
J Am Chem Soc. 2003 Jan 22;125(3):696-704
12526669
Nature. 1998 Aug 20;394(6695):798-801
9723621
J Biol Chem. 2001 Sep 7;276(36):33540-6
11432870
Annu Rev Biophys Biomol Struct. 2003;32:257-83
12543707
Biophys J. 1999 Apr;76(4):2142-57
10096908
Cell. 1992 Feb 7;68(3):533-44
1531449
Nature. 1998 Aug 20;394(6695):802-5
9723622
Proteins. 1999 Feb 15;34(3):383-94
10024024
Science. 1972 Feb 18;175(4023):720-31
4333397
Chem Phys Lipids. 2002 May;115(1-2):93-105
12047901
Nat Rev Mol Cell Biol. 2000 Oct;1(1):31-9
11413487
Chembiochem. 2001 Apr 2;2(4):265-71
11828454
Mol Cell Biol. 1999 Nov;19(11):7289-304
10523618
Biophys J. 2001 Nov;81(5):2707-15
11606283
Biochim Biophys Acta. 2003 Mar 10;1610(2):208-16
12648775
FEBS Lett. 2002 Oct 30;531(1):33-7
12401199
J Lipid Res. 1967 May;8(3):202-9
4962590
Chem Phys Lipids. 1977 Dec;20(4):273-84
597969
Nature. 1997 Jun 5;387(6633):569-72
9177342