2,5-oligoadenylate-peptide nucleic acids (2-5A-PNAs) activate RNase L.
To potentiate the 2-5A (2',5'-oligoadenylate)-antisense and peptide nucleic acid (PNA) approaches to regulation of gene expression, composite molecules were generated containing both 2-5A and PNA moieties. 2-5A-PNA adducts were synthesized using solid-phase techniques. Highly cross-linked polystyrene beads were functionalized with glycine tethered through a p-hydroxymethylbenzoic acid linker and the PNA domain of the chimeric oligonucleotide analogue was added by sequential elongation of the amino terminus with the monomethoxytrityl protected N-(2-aminoethyl)-N-(adenin-1-ylacetyl)glycinate. Transition to the 2-5A domain was accomplished by coupling of the PNA chain to dimethoxytrityl protected N-(2-hydroxyethyl)-N-(adenin-1-ylacetyl)glycinate. Finally, (2-cyanoethyl)-N,N-diisopropyl-4-O-(4,4-dimethoxytrityl)butylphosphor amidite and the corresponding (2-cyanoethyl)-N,N-diisopropylphosphoramidite of 5-O-(4,4'-dimethoxytrityl)-3-O-(tert-butyldimethylsilyl)-N6-benzoyladeno sine were the synthons employed to add the 2 butanediol phosphate linkers and the four 2',5'-linked riboadenylates. The 5'-phosphate moiety was introduced with 2-[[2-(4,4'-dimethoxytrityloxy)ethyl]sulfonyl]ethyl-(2-cyanoethyl) -N,N-diisopropylphosphoramidite. Deprotection with methanolic NH3 and tetraethylammonium fluoride afforded the desired products, 2-SA-pnaA4, 2-5A-pnaA8 and 2-5A-pnaA12. When evaluated for their ability to cause the degradation of two different RNA substrates by the 2-5A-dependent RNase L, these new 2-5A-PNA conjugates were found to be potent RNase L activators. The union of 2-5A and PNA presents fresh opportunities to explore the biological and therapeutic implications of these unique approaches to antisense.
Verheijen
J C
JC
Leiden Institute of Chemistry, Gorlaeus Laboratories, The Netherlands.
van der Marel
G A
GA
van Boom
J H
JH
Bayly
S F
SF
Player
M R
MR
Torrence
P F
PF
D000227:Adenine Nucleotides / Q000737:chemistry*; D002460:Cell Line; D004722:Endoribonucleases / Q000378:metabolism*; D004789:Enzyme Activation; D006801:Humans; D006868:Hydrolysis; D009843:Oligoribonucleotides / Q000737:chemistry*; D020135:Peptide Nucleic Acids / Q000737:chemistry / Q000494:pharmacology*; D011869:Radioligand Assay; D011994:Recombinant Proteins / Q000378:metabolism
D000227:Adenine Nucleotides; D009843:Oligoribonucleotides; D020135:Peptide Nucleic Acids; D011994:Recombinant Proteins; C023505:2',5'-oligoadenylate; D004722:Endoribonucleases; C031956:2-5A-dependent ribonuclease