posted on 2013-10-16, 00:00authored byPiret Arukuusk, Ly Pärnaste, Helerin Margus, N. K. Jonas Eriksson, Luis Vasconcelos, Kärt Padari, Margus Pooga, Ülo Langel
In the current work we characterize
the uptake mechanism of two
NickFect family members, NF51 and NF1, related to the biological activity
of transfected plasmid DNA (pDNA). Both vectors condense pDNA into
small negatively charged nanoparticles that transfect HeLa cells with
equally high efficacy and the delivery is mediated by SCARA3 and SCARA5
receptors. NF1 condenses DNA into less homogeneous and less stable
nanoparticles than NF51. NF51/pDNA nanoparticles enter the cells via
macropinocytosis, while NF1/pDNA complexes use clathrin- or caveolae-mediated
endocytosis and macropinocytosis. Analysis of separated endosomal
compartments uncovered lysomotropic properties of NF51 that was also
proven by cotransfection with chloroquine. In summary we characterize
how radical modifications in peptides, such as introducing a kink
in the structure of NF51 or including extra negative charge by phospho-tyrosine
substitution in NF1, resulted in equally high efficacy for gene delivery,
although this efficacy is achieved by using differential transfection
pathways.