Design and synthesis of the different ASOs used in the study. (A) The different chemical modalities used in this study can be grouped into three different categories: modifications of the phosphate backbone (gray), modifications of the ribose sugar (green), and alternative backbone chemistries (blue). The gray and green boxes comprise ASOs that bear net negative charges; ASOs in the blue box are charge-neutral. (B) The KFF-PNA conjugates were synthesized as fusion peptides on a peptide synthesizer. (C) Schematic for the strain-promoted alkyne–azide click reaction between the peptide (synthesized on a peptide synthesizer) and the ASO (synthesized on an oligonucleotide synthesizer). Created with BioRender.com.
