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Fluorescent Leakage Assay to Investigate Membrane Destabilization by Cell-Penetrating Peptide
Published on: December 19, 2020
Differential membrane perturbation caused by the cell penetrating peptide Tp10 depending on attached cargo
Elsa Bárány-Wallje1, Jugnu Gaur, Pontus Lundberg
1Department of Biochemistry and Biophysics, The Arrhenius Laboratories, Stockholm University, S-10691 Stockholm, Sweden.
Abstract:
The membrane leakage caused by the cell penetrating peptide Tp10, a variant of transportan, was studied in large unilamellar vesicles with the entrapped fluorophore calcein. The vesicles were composed of zwitterionic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine. A significant decrease in membrane leakage was found when the 55kDa streptavidin protein was attached to Tp10. When a 5.4kDa peptide nucleic acid molecule was attached, the membrane leakage was comparable to that caused by Tp10 alone. The results suggest that direct membrane effects may cause membrane translocation of Tp10 alone and of smaller complexes, whereas these effects do not contribute for larger cargoes.
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