Optical control of membrane mechanics via global and red-light-catalyzed, leaflet-selective photolipid switching

Azobenzene photolipids are known for their ability to manipulate membrane mechanics and protein function. However, controlling these effects using long-wavelength light and selectively targeting individual leaflets of the membrane has been challenging. In this study, researchers address these issues by demonstrating a new method for red-light-induced, reversible cis-trans photoisomerization of azobenzene photolipids, without the need for covalent bonding.

They also show that photocatalysis is primarily intraleaflet, allowing for leaflet-specific actuation by introducing the membrane-targeted chromophore into just one layer of the bilayer. This enables precise control of mechanical asymmetry within the membrane, which is tracked through lock-in capacitance measurements. By illuminating the membrane with blue or red light, researchers can induce both symmetric and asymmetric perturbations in mechanical properties within the same membrane.

Furthermore, they highlight the biocompatibility of this approach by demonstrating its impact on the ROS-sensitive mechanosensitive peptide ion channel gramicidin A. The findings present a new tool for studying the role of dynamic, leaflet-specific mechanical changes in membrane remodeling and protein function.