| Full text | |
| Author(s): |
de Mello, Lucas Rodrigues
[1]
;
Hamley, Ian William
[2]
;
Castelletto, Valeria
[2]
;
Moreno Garci, Bianca Bonetto
[1]
;
Han, Sang Won
[1]
;
Pinto de Oliveira, Cristiano Luis
[3]
;
da Silv, Emerson Rodrigo a
[1]
Total Authors: 7
|
| Affiliation: | [1] Univ Fed Sao Paulo, Dept Biofis, BR-04023062 Sao Paulo - Brazil
[2] Univ Reading, Dept Chem, Reading RGD 6AD, Berks - England
[3] Univ Sao Paulo, Inst Fis, BR-05508090 Sao Paulo - Brazil
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | Journal of Physical Chemistry B; v. 123, n. 42, p. 8861-8871, OCT 24 2019. |
| Web of Science Citations: | 0 |
| Abstract | |
One of the most remarkable examples of cell-penetrating peptides (CPPs) is Penetratin, a 16-mer fragment derived from the Drosophila Antennapedia homeobox. Understanding the structure of Penetratin/DNA complexes is a key factor for the successful design of new vectors for gene delivery and may assist in optimizing molecular carriers based on CPPs. Herein, we present a comprehensive study on the nanoscale structure of noncovalent complexes formed between Penetratin and DNA. The strong cationic nature of the peptide makes it a very efficient agent for condensing DNA strands via electrostatic attraction, and we show for the first time that DNA condensation is accompanied by random-to-beta-sheet transitions of Penetratin secondary structure, demonstrating that nucleic acids behave as a structuring agent upon complexation. For the first time, nanoscale-resolved spectroscopy is used to provide single-particle infrared data from DNA carriers based on CPPs, and they show that the structures are stabilized by Penetratin beta-sheet cores, whereas larger DNA fractions are preferentially located in the periphery of aggregates. In-solution infrared assays indicate that phosphate diester groups are strongly affected upon DNA condensation, presumably as a consequence of charge delocalization induced by the proximity of cationic amide groups in Penetratin. The morphology is characterized by nanoassemblies with surface fractal features, and short-range order is found in the inner structure of the scaffolds. Interestingly, the formation of beads-on-a-string arrays is found, producing nanoscale architectures that resemble structures observed in early steps of chromatin condensation. A complexation pathway where DNA condensation and peptide pairing into beta-sheets are key steps for organization is proposed. (AU) | |
| FAPESP's process: | 15/20206-8 - Modulation of monocytes, macrophages and pericytes by the colony stimulating factor genes to treat murine limb ischemia |
| Grantee: | Sang Won Han |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 16/24409-3 - Cell-Penetrating Peptides for Transport of Plasmid DNA and microRNA: from Nanoscopic Structure to Gene Delivery. |
| Grantee: | Emerson Rodrigo da Silva |
| Support Opportunities: | Regular Research Grants |