Alignment of cholesterol in the membrane bilayer.
Freeze-fracture replicas of filipin-treated samples of guinea pig colon mucosa reveal areas in the membrane of the goblet cell granules labeled by filipin-cholesterol complexes (FCC) intermingled with regions patterned by "lines." The FCC and "lines" are arranged in an approximately rhombic pattern. Other membranes of the same cell or of other cells display either FCC only, aligned and occasionally ordered in "rhombs," "lines" only, with a similar pattern, or randomly distributed FCC. Optical diffraction was used to analyze and compare replicas of membranes with ordered FCC and "lines", as well as randomly distributed FCC. The results demonstrate that all these structures are reciprocally related through a common distribution pattern in the membrane. This observation supports the assumption that cholesterol has a preferential ordered distribution within the membrane bilayer.
Laboratory of Cell Biology and Electron Microscopy, Hannover Medical School, Federal Republic of Germany.
L
L
Luciano
E
E
Reale
H
H
Konitz
U
U
Boseck
S
S
Boseck
D000818:Animals; D002462:Cell Membrane / Q000032:analysis / Q000648:ultrastructure; D002784:Cholesterol / Q000032:analysis* / Q000378:metabolism; D003106:Colon / Q000032:analysis / Q000166:cytology* / Q000648:ultrastructure; D005372:Filipin / Q000032:analysis / Q000378:metabolism; D005614:Freeze Fracturing; D006168:Guinea Pigs; D007413:Intestinal Mucosa / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D008854:Microscopy, Electron; D009092:Mucous Membrane / Q000378:metabolism / Q000648:ultrastructure; D014961:X-Ray Diffraction
D005372:Filipin; D002784:Cholesterol