Behavior of a photoactivatable analog of cholesterol, 6-photocholesterol, in model membranes.
6-Photocholesterol, a new photoactivatable analog of cholesterol in which a diazirine functionality replaces the 5,6-double bond in the steroid nucleus, was used recently to identify cholesterol-binding proteins in neuroendocrine cells [Thiele, C., Hannah, M.J., Farenholz, F. and Huttner, W.B. (2000) Nat. Cell Biol. 2, 42-49], to track the distribution and transport of cholesterol in Caenorhabditis elegans [Matyash, V., Geier, C., Henske, A., Mukherjee, S., Hirsh, D., Thiele, C., Grant, B., Maxfield, F.R. and Kurzchalia, T.V. (2001) Mol. Biol. Cell 12, 1725-1736], and to probe lipid-protein interactions in oligodendrocytes [Simons, M., Kramer, E.M., Thiele, C., Stoffel, W. and Trotter, J. (2000) J. Cell Biol. 151, 143-154]. To determine whether 6-photocholesterol is a faithful mimetic of cholesterol we analyzed the ability of this probe, under conditions in which it is not photoactivated to a carbene, to substitute for cholesterol in two unrelated assays: (1) to condense 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine monomolecular films and (2) to mediate the fusion of two alphaviruses (Semliki Forest and Sindbis) with liposomes. The results suggest that this analog is a suitable photoprobe of cholesterol.
Mintzer
Evan A
EA
Department of Chemistry and Biochemistry, Queens College of the City University of New York, Flushing, 13367, USA.
Waarts
Barry-Lee
BL
Wilschut
Jan
J
Bittman
Robert
R
D002784:Cholesterol / Q000031:analogs & derivatives* / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008051:Lipid Bilayers / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry; D008561:Membrane Fusion / Q000502:physiology; D008567:Membranes, Artificial; D008954:Models, Biological; D015335:Molecular Probes / Q000737:chemistry; D010713:Phosphatidylcholines / Q000737:chemistry; D010777:Photochemistry / Q000379:methods*; D012672:Semliki forest virus / Q000737:chemistry / Q000378:metabolism; D012845:Sindbis Virus / Q000737:chemistry / Q000378:metabolism; D013261:Sterols / Q000737:chemistry
C445541:6-photocholesterol; D008051:Lipid Bilayers; D008081:Liposomes; D008567:Membranes, Artificial; D015335:Molecular Probes; D010713:Phosphatidylcholines; D013261:Sterols; D002784:Cholesterol; C028694:1-palmitoyl-2-oleoylphosphatidylcholine