Peptide nucleic acids are potent modulators of endogenous pre-mRNA splicing of the murine interleukin-5 receptor-alpha chain.
Antisense oligonucleotides (ASOs) that bind target pre-mRNA with high affinity have been shown to alter splicing patterns and offer promise as therapeutics. Previous studies have shown that ASOs fully modified with 2'-O-methoxyethyl (2'-O-MOE) sugar residues redirect constitutive and alternative splicing of the murine interleukin-5 receptor-alpha (IL-5Ralpha) chain pre-mRNA in cells, resulting in inhibition of the membrane-bound isoform and enhanced expression of the soluble isoform. Here, we show that antisense peptide nucleic acids (PNAs) alter splicing of the IL-5Ralpha pre-mRNA in a fashion similar to their 2'-O-MOE-modified counterparts of the same sequence. Moreover, using PNA as the splicing modulator, the length of the antisense oligomer could be shortened from 20 to 15 nucleobase units to obtain a comparable effect. Treatment of cells with antisense PNA resulted in dose-dependent, specific downregulation of IL-5Ralpha membrane isoform mRNA expression and enhanced levels of the soluble IL-5Ralpha isoform transcript, with an EC50 equivalent to that observed in parallel with the corresponding 2'-O-MOE ASO. The pronounced activity of antisense PNAs in modulating IL-5Ralpha mRNA splicing observed in our study identifies these compounds as a promising new class of lower molecular weight splicing modulators.
Karras
J G
JG
Department of Molecular and Cellular Pharmacology, ISIS Pharmaceuticals, Incorporated, 2292 Faraday Avenue, Carlsbad, California 92008, USA.
Maier
M A
MA
Lu
T
T
Watt
A
A
Manoharan
M
M
D017398:Alternative Splicing / Q000187:drug effects*; D000818:Animals; D001483:Base Sequence; D051379:Mice; D016376:Oligonucleotides, Antisense / Q000138:chemical synthesis / Q000494:pharmacology; D020135:Peptide Nucleic Acids / Q000138:chemical synthesis / Q000494:pharmacology*; D012322:RNA Precursors / Q000378:metabolism*; D018123:Receptors, Interleukin / Q000235:genetics* / Q000378:metabolism*; D053649:Receptors, Interleukin-5; D013873:Thionucleotides / Q000138:chemical synthesis / Q000494:pharmacology; D014162:Transfection; D014407:Tumor Cells, Cultured
D016376:Oligonucleotides, Antisense; D020135:Peptide Nucleic Acids; D012322:RNA Precursors; D018123:Receptors, Interleukin; D053649:Receptors, Interleukin-5; D013873:Thionucleotides