Fig. 3.

The induction of saddle-splay curvature alone is not a sufficient condition for full strength CPP activity. (A) TAMRA-labeled TAT peptide (TAMRA-TAT; red) readily crossed the membrane of PS∶PC∶PE = 20∶40∶40 GUVs. (B) TAT peptide covalently coupled to Cy5-tagged PLA nanoparticles (TAT-NP, approximately 30-nm diameter, blue) did not cross the membrane but were localized at the periphery of GUVs. (C) PS∶PC∶PE = 20∶40∶40 GUVs loaded with G-actin and rhodamine phalloidin (red). (D) TAT-NPs (blue), added to these GUVs and localized at the periphery, were able to induce negative Gaussian membrane curvature and membrane permeation, enabling Mg²⁺ ions to cross GUV membrane and polymerize the encapsulated G-actin into F-actin bundles (red). White scale bars are 10 μm.