S4(13)-PV cell-penetrating peptide induces physical and morphological changes in membrane-mimetic lipid systems and cell membranes: implications for cell internalization.
The present work aims to gain insights into the role of peptide-lipid interactions in the mechanisms of cellular internalization and endosomal escape of the S4(13)-PV cell-penetrating peptide, which has been successfully used in our laboratory as a nucleic acid delivery system. A S4(13)-PV analogue, S4(13)-PVscr, displaying a scrambled amino acid sequence, deficient cell internalization and drug delivery inability, was used in this study for comparative purposes. Differential scanning calorimetry, fluorescence polarization and X-ray diffraction at small and wide angles techniques showed that both peptides interacted with anionic membranes composed of phosphatidylglycerol or a mixture of this lipid with phosphatidylethanolamine, increasing the lipid order, shifting the phase transition to higher temperatures and raising the correlation length between the bilayers. However, S4(13)-PVscr, in contrast to the wild-type peptide, did not promote lipid domain segregation and induced the formation of an inverted hexagonal lipid phase instead of a cubic phase in the lipid systems assayed. Electron microscopy showed that, as opposed to S4(13)-PVscr, the wild-type peptide induced the formation of a non-lamellar organization in membranes of HeLa cells. We concluded that lateral phase separation and destabilization of membrane lamellar structure without compromising membrane integrity are on the basis of the lipid-driven and receptor-independent mechanism of cell entry of S4(13)-PV peptide. Overall, our results can contribute to a better understanding of the role of peptide-lipid interactions in the mechanisms of cell-penetrating peptide membrane translocation, helping in the future design of more efficient cell-penetrating peptide-based drug delivery systems.
Centre for Neuroscience and Cell Biology, University of Coimbra, Portugal.
Ana M S
AM
Cardoso
Sara
S
Trabulo
Ana L
AL
Cardoso
Annely
A
Lorents
Catarina M
CM
Morais
Paula
P
Gomes
Cláudia
C
Nunes
Marlene
M
Lúcio
Salette
S
Reis
Kärt
K
Padari
Margus
M
Pooga
Maria C
MC
Pedroso de Lima
Amália S
AS
Jurado
D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D057846:Cell-Penetrating Peptides / Q000737:chemistry* / Q000493:pharmacokinetics* / Q000494:pharmacology; D016503:Drug Delivery Systems / Q000379:methods; D006367:HeLa Cells; D006801:Humans; D008051:Lipid Bilayers / Q000737:chemistry* / Q000378:metabolism; D010455:Peptides / Q000737:chemistry* / Q000493:pharmacokinetics* / Q000494:pharmacology; D010714:Phosphatidylethanolamines / Q000737:chemistry / Q000378:metabolism; D010715:Phosphatidylglycerols / Q000737:chemistry / Q000378:metabolism
D057846:Cell-Penetrating Peptides; D008051:Lipid Bilayers; D010455:Peptides; D010714:Phosphatidylethanolamines; D010715:Phosphatidylglycerols; C512366:S4(13)-PV peptide; C483858:phosphatidylethanolamine