Protein nanodisk assembling and intracellular trafficking powered by an arginine-rich (R9) peptide.
OBJECTIVE
Arginine(R)-rich cationic peptides are powerful tools in drug delivery since, alone or when associated with polyplexes, proteins or chemicals, they confer DNA condensation, membrane translocation and blood-brain barrier crossing abilities. The unusual stability and high in vivo performance of their associated drugs suggest a particulate organization or R(n) complexes, which this study aimed to explore.


METHODS
We have analyzed the particulate organization and biological performance in DNA delivery of a model, R9-containing green fluorescent protein by dynamic light scattering, transmission electron microscopy, atomic force microscopy, single cell confocal microscopy and flow cytometry.


RESULTS
A deep nanoscale examination of R9-powered constructs reveals a novel and promising feature of R9, that when fused to a scaffold green fluorescent protein, promote its efficient self-assembling as highly stable, regular disk-shaped nanoparticles of 20 x 3 nm. These constructs are efficiently internalized in mammalian cells and rapidly migrate through the cytoplasm towards the nucleus in a fully bioactive form. Besides, such particulate platforms accommodate, condense and deliver plasmid DNA to the nucleus and promote plasmid-driven transgene expression.


CONCLUSIONS
The architectonic properties of arginine-rich peptides at the nanoscale reveal a new category of protein nanoparticles, namely nanodisks, and provide novel strategic concepts and architectonic tools for the tailored construction of new-generation artificial viruses for gene therapy and drug delivery.
Institute for Biotechnology and Biomedicine, Department of Genetics and Microbiology, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.
Esther
E
Vazquez
Mónica
M
Roldán
César
C
Diez-Gil
Ugutz
U
Unzueta
Joan
J
Domingo-Espín
Juan
J
Cedano
Oscar
O
Conchillo
Imma
I
Ratera
Jaume
J
Veciana
Xavier
X
Daura
Neus
N
Ferrer-Miralles
Antonio
A
Villaverde
D001120:Arginine / Q000737:chemistry*; D001812:Blood-Brain Barrier; D002412:Cations; D004247:DNA / Q000737:chemistry / Q000235:genetics; D005434:Flow Cytometry / Q000379:methods; D005456:Fluorescent Dyes / Q000494:pharmacology; D018014:Gene Transfer Techniques; D049452:Green Fluorescent Proteins / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D018625:Microscopy, Atomic Force / Q000379:methods; D046529:Microscopy, Electron, Transmission / Q000379:methods; D053761:Nanocomposites / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*
D002412:Cations; D005456:Fluorescent Dyes; D010455:Peptides; D049452:Green Fluorescent Proteins; D004247:DNA; D001120:Arginine