Effect of small molecule signaling in PepFect14 transfection.

Cell-penetrating peptides can be used to deliver oligonucleotide-based cargoes into cells. Previous studies have shown that the use of small molecule drugs could be an efficient method to increase the efficacy of delivery of oligonucleotides by cell-penetrating peptides either as targeting agents that can be used in formulation with the cell-penetrating peptide and its cargo or as cell signaling modulators that facilitates the cellular uptake of the treatment. This study presents two aims.

A High-Throughput Kinetic Assay for RNA-Cleaving Deoxyribozymes.

Determining kinetic constants is important in the field of RNA-cleaving deoxyribozymes (DNAzymes). Using todays conventional gel assays for DNAzyme assays is time-consuming and laborious. There have been previous attempts at producing new and improved assays; however these have drawbacks such as incompatibility with structured DNAzymes, enzyme or substrate modifications and increased cost.

SCARA Involvement in the Uptake of Nanoparticles Formed by Cell-Penetrating Peptides.

The investigation of uptake mechanisms for cell-penetrating peptides (CPPs) is and has been an ongoing project for as long as the peptides have been known, a time period that now spans over two decades. The ultimate answer is yet to be revealed and the current understanding is that no "one" mechanism will ever be found. The reason for this is that the uptake mechanism seems to be dependent on a multitude of factors that include which CPP, what cells are used, whether or not there is cargo and what the cargo is.

Optimized luciferase assay for cell-penetrating peptide-mediated delivery of short oligonucleotides.

An improved assay for screening for the intracellular delivery efficacy of short oligonucleotides using cell-penetrating peptides is suggested. This assay is an improvement over previous assays that use luciferase reporters for cell-penetrating peptides because it has been scaled up from a 24-well format to a 96-well format and no longer relies on a luciferin reagent that has been commercially sourced. In addition, the homemade luciferin reagent is useful in multiple cell lines and in different assays that rely on altering the expression of luciferase.

Dendritic glutamate receptor mRNAs show contingent local hotspot-dependent translational dynamics.

Protein synthesis in neuronal dendrites underlies long-term memory formation in the brain. Local translation of reporter mRNAs has demonstrated translation in dendrites at focal points called translational hotspots. Various reports have shown that hundreds to thousands of mRNAs are localized to dendrites, yet the dynamics of translation of multiple dendritic mRNAs has remained elusive.

PepFect15, a novel endosomolytic cell-penetrating peptide for oligonucleotide delivery via scavenger receptors.

Gene-regulatory biomolecules such as splice-correcting oligonucleotides and anti-microRNA oligonucleotides are important tools in the struggle to understand and treat genetic disorders caused by defective gene expression or aberrant splicing. However, oligonucleotides generally suffer from low bioavailability, hence requiring efficient and non-toxic delivery vectors to reach their targets. Cell-penetrating peptides constitute a promising category of carrier molecules for intracellular delivery of bioactive cargo.

Scavenger receptor-mediated uptake of cell-penetrating peptide nanocomplexes with oligonucleotides.

Cell-penetrating peptides (CPPs) are short cationic peptides that penetrate cells by interacting with the negatively charged plasma membrane; however, the detailed uptake mechanism is not clear. In contrary to the conventional mode of action of CPPs, we show here that a CPP, PepFect14 (PF14), forms negatively charged nanocomplexes with oligonucleotides and their uptake is mediated by class-A scavenger receptors (SCARAs). Specific inhibitory ligands of SCARAs, such as fucoidin, polyinosinic acid, and dextran sulfate, totally inhibit the activity of PF14-oligonucleotide nanocomplexes in the HeLa pLuc705 splice-correction cell model, while nonspecific, chemically related molecules do not.