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Sequence-specific and Selective Recognition of Double-stranded RNAs over Single-stranded RNAs by Chemically Modified Peptide Nucleic Acids
Published on: September 21, 2017
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Pyrene-modified PNAs: Stacking interactions and selective excimer emission in PNA2DNA triplexes
Alex Manicardi1, Lucia Guidi1, Alice Ghidini2
1Department of Chemistry, University of Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy. ; Tel: +39 0521 905410.
Beilstein Journal of Organic Chemistry
|August 28, 2014
Summary
Synthesized peptide nucleic acids (PNAs) with pyrene units enable sequence-selective DNA detection. PNA2, with two pyrene units, showed enhanced triplex stability and high mismatch selectivity for cystic fibrosis mutation detection.
Area of Science:
- Biochemistry
- Organic Chemistry
- Molecular Biology
Background:
- Pyrene derivatives are utilized in nucleic acid analogs for switchable probes and supramolecular assemblies.
- Peptide nucleic acids (PNAs) offer unique structural properties for DNA recognition.
Purpose of the Study:
- To synthesize and characterize pyrene-containing PNA probes for detecting specific DNA sequences.
- To investigate the impact of pyrene unit incorporation on PNA-DNA triplex formation and stability.
- To evaluate the diagnostic potential of these probes for the cystic fibrosis W1282X mutation.
Main Methods:
- Synthesis of peptide nucleic acids (PNAs) with varying numbers and positions of 1-pyreneacetic acid units (PNA1-6).
- Characterization of PNA-DNA triplex formation using fluorescence spectroscopy to monitor pyrene excimer emission.
- Assessment of triplex stability and mismatch selectivity through binding assays.
Main Results:
- Pyrene-containing PNAs demonstrated sequence-selective 'switch-on' of pyrene excimer fluorescence upon binding to complementary DNA targets.
- PNA2, featuring two strategically positioned pyrene units, exhibited enhanced PNA2DNA triplex stability.
- High mismatch selectivity was observed, attributed to combined base-pairing and stacking interactions.
Conclusions:
- Pyrene-functionalized PNAs serve as effective probes for sequence-specific DNA detection.
- The number and placement of pyrene units significantly influence PNA2DNA triplex stability and probe selectivity.
- The developed PNA probes show promise for sensitive and selective detection of genetic mutations, such as the cystic fibrosis W1282X point mutation.
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