Visualization of ceramide channels by transmission electron microscopy.
Functional studies have shown that the sphingolipid ceramide, self-assembles in phospholipid membranes to form large channels capable of allowing proteins to cross the membrane. Here these channels are visualized by negative stain transmission electron microscopy. The images contain features consistent with stain-filled pores having a roughly circular profile. There is no indication of tilt, and the results are consistent with the formation of right cylinders. The sizes of the pores range from 5 to 40nm in diameter with an asymmetric distribution indicating no apparent upper size limit. The size distribution matches well with the distribution of sizes calculated from electrophysiological measurements.
Department of Biology, University of Maryland, College Park, MD 20742, USA.
Soumya
S
Samanta
Johnny
J
Stiban
Timothy K
TK
Maugel
Marco
M
Colombini
D002462:Cell Membrane / Q000737:chemistry* / Q000648:ultrastructure; D002463:Cell Membrane Permeability; D002518:Ceramides / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry / Q000648:ultrastructure; D008563:Membrane Lipids / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D008958:Models, Molecular
D002518:Ceramides; D008081:Liposomes; D008563:Membrane Lipids
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