Fluorogenic PNA probes

Abstract

Fluorogenic oligonucleotide probes that can produce a change in fluorescence signal upon binding to specific biomolecular targets, including nucleic acids as well as non-nucleic acid targets, such as proteins and small molecules, have applications in various important areas. These include diagnostics, drug development and as tools for studying biomolecular interactions in situ and in real time. The probes usually consist of a labeled oligonucleotide strand as a recognition element together with a mechanism for signal transduction that can translate the binding event into a measurable signal. While a number of strategies have been developed for the signal transduction, relatively little attention has been paid to the recognition element. Peptide nucleic acids (PNA) are DNA mimics with several favorable properties making them a potential alternative to natural nucleic acids for the development of fluorogenic probes, including their very strong and specific recognition and excellent chemical and biological stabilities in addition to their ability to bind to structured nucleic acid targets. In addition, the uncharged backbone of PNA allows for other unique designs that cannot be performed with oligonucleotides or analogues with negatively-charged backbones. This review aims to introduce the principle, showcase state-of-the-art technologies and update recent developments in the areas of fluorogenic PNA probes during the past 20 years.

Analysis of Single Nucleotide-Mutated Single-Cancer Cells Using the Combined Technologies of Single-Cell Microarray Chips and Peptide Nucleic Acid-DNA Probes

“…This study used DAPI for staining the cellular nucleus, PE-labeled anti-CK antibody for staining the CK, and an FITC-conjugated PNA-DNA probe for staining the T790M-mutated EGFR mRNA. PNA has high target binding ability due to PNA’s lack of electronic charge in the backbone and has the high specificity [ 49 , 50 , 51 , 52 ]. These PNA probes are expected to be more suitable than DNA probes for gene mutation analysis of single-nucleotide mutations.…”

“…PNA has high target binding ability due to PNA's lack of electronic charge in the backbone and has the high specificity [49][50][51][52]. These PNA probes are expected to be more suitable than DNA probes for gene mutation analysis of single-nucleotide mutations.…”

PNA-Based MicroRNA Detection Methodologies

“…Fluorescent PNA probes are reported for a wide range of sensing applications [76]. Focusing on fluorescence-based methodologies developed for miR detection, there are several examples in literature where PNA beacons are used for in vivo imaging of miR.…”

Applications of Ruthenium Complexes Covalently Linked to Nucleic Acid Derivatives

“…Thereby, synthetic ways to chemically modify nucleic acids analogues have been developed over the past decades in order to obtain a better understanding of the role of DNA in various biological mechanisms or to add unexpected properties to natural processes [ 22 ]. For instance, oligonucleotides containing a peptide backbone (peptide nucleic acids, PNA) [ 23 , 24 , 25 , 26 , 27 ], unnatural bases [ 19 , 28 , 29 , 30 , 31 ], or altered phosphate groups [ 32 , 33 ] have been reported.…”