Cell-Permeable Peptide Nucleic Acid Designed to Bind to the 5‘-Untranslated Region of E-cadherin Transcript Induces Potent and Sequence-Specific Antisense Effects

Abstract

Establishing a general and effective method for regulating gene expression in mammalian systems is important for many aspects of biological and biomedical research. Herein we report the antisense activities of a cell-permeable, guanidine-based peptide nucleic acid (PNA) called GPNA. We show that a GPNA oligomer designed to bind to the transcriptional start-site of human E-cadherin gene induces potent and sequence-specific antisense effects and is less toxic to the cells than the corresponding PNA-polyarginine conjugate. GPNA confers its silencing effect by blocking protein translation. The findings reported in this study provide a molecular framework for designing the next generation cell-permeable nucleic acid mimics for regulating gene expression in live cells and intact organisms.

Insights on chiral, backbone modified peptide nucleic acids: Properties and biological activity

“…90 PNA containing arginine residues (GPNA) were more easily taken up by mammalian cell and resulted in being less toxic compared to PNA and PNA conjugated with polyarginine. 91 GPNAs were successfully used to target the transcriptional start site of E-cadherin gene producing a sequence-specific antisense effect. 91 GPNAs were also employed for PNA microarray analysis and their higher sequence selectivity in this context was demonstrated.…”

“…91 GPNAs were successfully used to target the transcriptional start site of E-cadherin gene producing a sequence-specific antisense effect. 91 GPNAs were also employed for PNA microarray analysis and their higher sequence selectivity in this context was demonstrated. 92 PNAs modified with bulky amino acids, such as His, Tyr, Trp, Phe and Val, furnished lower T m compared to the unsubstituted ones, due to their substantially larger steric hindrance.…”

Nucleic Acid-programmed Assemblies: Translating Instruction into Function in Chemical Biology

“…Using a first order approximation, a rate constant (k) of 2.76 × 10 was calculated for the Staudinger unquenching of bis-azidorhodamine (Fig 8). [78] To perform the reaction in live cells, GPNA [17] endowed with cellular permeability were used. This enabled the detection of mRNA in live cells using the azidorhodamine fluorophore.…”

“…[16] An important example of these modifications is the incorporation of d-arginine instead of glycine providing a guanidinium group at the C(2) (α position) of a PNA monomer (so called GPNA) . [17] Oligomers containing four or more GPNA residues have been shown to be cell permeable and have moderately enhanced affinity. Another important modification is at the C(5) (γ position) with the side chain of diverse l-amino acids.…”

A Peptide Nucleic Acid Embedding a Pseudopeptide Nuclear Localization Sequence in the Backbone Behaves as a Peptide Mimic

“…Although the introduction of substituents in the PNA backbone has been used to introduce functional groups and charges (thus modulating the properties of the PNAs), [5][6][7] the use of side chains mimicking an entire complex peptide consensus sequence with a specific biological function has never been reported, and this represents a challenging task both conceptually and synthetically.…”