Optical Control of Lipid Rafts with Photoswitchable Ceramides

Frank, James Allen; Franquelim, Henri G.; Schwille, Petra and Trauner, Dirk (2016): Optical Control of Lipid Rafts with Photoswitchable Ceramides. In: Journal of the American Chemical Society, Vol. 138, No. 39: pp. 12981-12986

Abstract

Ceramide is a pro-apoptotic sphingolipid with unique physical characteristics. Often viewed as a second messenger, its generation can modulate the structure of lipid rafts. We prepared three photoswitchable ceramides, Aces, which contain an azobenzene photoswitch allowing for, optical control over the N-acyl chain. Using combined atomic force and confocal fluorescence microscopy, we demonstrate that the ACes enable reversible switching of lipid domains in raft-mimicking supported lipid bilayers (SLBs). In the trans configuration, the ACes localize into the liquid-ordered (L-o) phase. Photoisomerization to the cis-form triggers a fluidification of the L. domains, as liquid-disordered (L-d) "lakes" are formed within the rafts. Photoisomerization back to the trans-state with blue light stimulates a rigidification inside the L-d phase, as the formation of small L. domains. These changes can be repeated over multiple cycles, enabling a dynamic spatiotemporal control of the lipid raft structure with light.

• Item Type: Journal article
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Subjects: 500 Science > 540 Chemistry
• ISSN: 0002-7863
• Language: English