Transcription factor decoy molecules based on a peptide nucleic acid (PNA)-DNA chimera mimicking Sp1 binding sites.
Peptide nucleic acids (PNAs) are DNA-mimicking molecules in which the sugar-phosphate backbone is replaced by a pseudopeptide backbone composed of N-(2-aminoethyl)glycine units. We determined whether double-stranded molecules based on PNAs and PNA-DNA-PNA (PDP) chimeras could be capable of stable interactions with nuclear proteins belonging to the Sp1 transcription factor family and, therefore, could act as decoy reagents able to inhibit molecular interactions between Sp1 and DNA. Since the structure of PNA/PNA hybrids is very different from that of the DNA/DNA double helix, they could theoretically alter the molecular structure of the double-stranded PNA-DNA-PNA chimeras, perturbing interactions with specific transcription factors. We found that PNA-based hybrids do not inhibit Sp1/DNA interactions. In contrast, hybrid molecules based on PNA-DNA-PNA chimeras are very effective decoy molecules, encouraging further experiments focused on the possible use of these molecules for the development of potential agents for a decoy approach in gene therapy. In this respect, the finding that PDP-based decoy molecules are more resistant than DNA/DNA hybrids to enzymatic degradation appears to be of great interest. Furthermore, their resistance can even be improved after complexation with cationic liposomes to which PDP/PDP chimeras are able to bind by virtue of their internal DNA structure.
Borgatti
Monica
M
Department of Biochemistry and Molecular Biology, Ferrara University, Via L.Borsari n.46, 44100 Ferrara, Italy.
Lampronti
Ilaria
I
Romanelli
Alessandra
A
Pedone
Carlo
C
Saviano
Michele
M
Bianchi
Nicoletta
N
Mischiati
Carlo
C
Gambari
Roberto
R
D001665:Binding Sites; D002467:Cell Nucleus / Q000378:metabolism; D006801:Humans; D020014:K562 Cells; D008081:Liposomes / Q000378:metabolism; D009841:Oligonucleotides / Q000494:pharmacology; D020135:Peptide Nucleic Acids / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016329:Sp1 Transcription Factor / Q000737:chemistry* / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism*; D014162:Transfection
D008081:Liposomes; D009841:Oligonucleotides; D020135:Peptide Nucleic Acids; D011993:Recombinant Fusion Proteins; D016329:Sp1 Transcription Factor; D014157:Transcription Factors