Lipid domain formation and membrane shaping by C24-ceramide
A E Ventura1, A R P Varela2, T Dingjan3
1Research Institute for Medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, Portugal; iBB-Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, Lisboa, Portugal; Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.
Biochimica Et Biophysica Acta. Biomembranes
|June 23, 2020
Summary
Very-long acyl chain ceramides, like C24-ceramide, significantly alter biological membrane structure and fluidity. These changes, including domain formation and vesicle shape modification, may trigger cellular processes.
Area of Science:
- Biochemistry
- Cell Biology
- Membrane Biophysics
Background:
- Sphingolipids, including ceramides, are crucial for cellular functions.
- Ceramides influence cellular events by modulating membrane biophysical properties.
- The precise mechanisms of ceramide action on membranes are not fully understood.
Purpose of the Study:
- To investigate the biophysical effects of very-long acyl chain C24-ceramide on fluid model membranes.
- To characterize ceramide-induced changes under both equilibrium and non-equilibrium conditions.
Main Methods:
- Utilized a fluid model membrane system.
- Analyzed membrane properties under thermodynamic equilibrium and non-equilibrium states.
- Characterized domain formation and vesicle morphology changes.
Main Results:
- C24-ceramide formed distinct gel domains, likely metastable interdigitated phases.
- At equilibrium, a partially interdigitated gel phase coexisted with the fluid phase.
- Observed significant vesicle shape alterations, including sharp-edged domains and tubules.
Conclusions:
- Very-long acyl chain ceramides induce substantial changes in membrane organization and fluidity.
- These alterations in biological membranes may be responsible for activating cellular processes.
- Initial formation of C24-ceramides during stress responses could initiate diverse cellular signaling pathways.
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