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Published on: June 23, 2023
Visualization of ceramide channels by transmission electron microscopy
Soumya Samanta1, Johnny Stiban, Timothy K Maugel
1Department of Biology, University of Maryland, College Park, MD 20742, USA.
Biochimica Et Biophysica Acta
|January 25, 2011
Summary
Ceramide self-assembles in membranes to create protein-transporting channels. Transmission electron microscopy visualized these pores, revealing right cylindrical structures consistent with prior electrophysiological data.
Area of Science:
- Biophysics
- Membrane Biology
- Structural Biology
Background:
- Sphingolipids, like ceramide, are crucial membrane components.
- Functional studies suggest ceramide forms channels for protein transport across membranes.
Purpose of the Study:
- To visualize ceramide-induced channels in phospholipid membranes.
- To characterize the structural properties and size distribution of these channels.
Main Methods:
- Negative stain transmission electron microscopy (TEM) was employed.
- Image analysis focused on pore profiles and structural integrity.
Main Results:
- TEM images revealed stain-filled pores with roughly circular profiles.
- Structures were consistent with right cylinders, lacking tilt.
- Pore diameters ranged from 5 to 40 nm, with no upper size limit observed.
- Observed size distribution correlated well with electrophysiological measurements.
Conclusions:
- Ceramide self-assembly forms protein-permeable channels in membranes.
- Negative stain TEM provides direct visualization of these channel structures.
- The structural findings support functional and electrophysiological data on ceramide channels.
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