Long-chain GM1 gangliosides alter transmembrane domain registration through interdigitation

Manna, Moutusi; Javanainen, Matti; Monne, Hector Martinez-Seara; Gabius, Hans-Joachim; Rog, Tomasz and Vattulainen, Ilpo (2017): Long-chain GM1 gangliosides alter transmembrane domain registration through interdigitation. In: Biochimica et Biophysica Acta-Biomembranes, Vol. 1859, No. 5: pp. 870-878

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.

• Item Type: Journal article
• Faculties: Veterinary Medicine
• Subjects: 600 Technology > 610 Medicine and health
• ISSN: 0005-2736
• Language: English