Local Deformation in Phase-Separated Giant Liposomes via Photo-Induced Peptide Nanofiber Formation

Dynamic morphology changes in cellular systems are achieved through spatiotemporal control of cytoskeletal assembly at the plasma membrane, such as pseudopodia formation in amoeba. Inspired by this biological system, we developed a phase-separated giant liposome system that enables reversible local deformation via spatiotemporal control of peptide nanofiber formation. Spiropyran (SP)/merocyanine (MC)-modified β-sheet-forming peptides (FKFECSP/MCKFE and FKFECSP/MCKFEHHHHHH) selectively localize in the liquid-disordered (Ld) phase of a phase-separated giant liposome via the coordination of His-tag with a Ni-NTA-modified lipid. Interestingly, upon visible light irradiation of the MC form of the peptides encapsulated in the phase-separated giant liposome, nanofiber polymerization is induced at the Ld phase to generate pseudopodia-like local deformation in the giant liposome. In contrast, UV light irradiation of the SP form of the peptides restores the giant liposome morphology to spherical. The developed system demonstrates a novel strategy for developing artificial systems that replicate the dynamic local deformation observed in living cells.