Abstract
Extracellular and cytosolic leaflets in cellular membranes are distinctly different in lipid composition, yet they contribute together to signaling across the membranes. Here we consider a mechanism based on long-chain gangliosides for coupling the extracellular and cytosolic membrane leaflets together. Based on atomistic molecular dynamics simulations, we find that long-chain GM1 in the extracellular leaflet exhibits a strong tendency to protrude into the opposing bilayer leaflet. This interdigitation modulates the order in the cytosolic monolayer and thereby strengthens the interaction and coupling across a membrane. Coarse-grained simulations probing longer time scales in large membrane systems indicate that GM1 in the extracellular leaflet modulates the phase behavior in the cytosolic monolayer. While short-chain GM1 maintains phase-symmetric bilayers with a strong membrane registration effect, the situation is altered with long-chain GM1. Here, the significant interdigitation induced by long-chain GM1 modulates the behavior in the cytosolic GM1-free leaflet, weakening and slowing down the membrane registration process. The observed physical interaction mechanism provides a possible means to mediate or foster transmembrane communication associated with signal transduction.
Original language | English |
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Pages (from-to) | 870-878 |
Number of pages | 9 |
Journal | Biochimica et Biophysica Acta: Biomembranes |
Volume | 1859 |
Issue number | 5 |
DOIs | |
Publication status | Published - 1 May 2017 |
Publication type | A1 Journal article-refereed |
Keywords
- cholesterol
- computer simulations
- Glycosphingolipid
- membrane domain
- membrane registry
- molecular dynamics
Publication forum classification
- Publication forum level 1
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Cell Biology