title: Comparative inhibition of ras p21 protein synthesis with phosphorus-modified antisense oligonucleotides.
abstract: A rabbit reticulocyte lysate translation assay was used to quantitatively compare a series of antisense oligodeoxyribonucleotides (11-mers) having different internucleoside linkages and various degrees of complementarity (100-80%) with the start codon and downstream 8 bases of Balb-ras p21 mRNA. The oligomers had either contiguous phosphodiester, or alternating methylphosphonate-phosphodiester, or contiguous methylphosphonate, or contiguous phosphorothioate linkages. Under the conditions used for the assay, all of the test compounds when present in about 10(3)-10(4) excess over mRNA (15 nM mRNA) inhibited protein synthesis to a degree which was dependent on both the concentration and sequence of the oligomer. At low concentrations (12.5-25 microM), the phosphorothioate analogs were the most potent inhibitors of p21 protein synthesis; however, a sequence non-specific effect for these oligomers was dominant at higher concentrations of oligomer (100-200 microM). The methylphosphonate oligomers appeared to be slightly more discriminant. Relative hybridization strengths were assessed by melting (Tm) studies using a DNA oligomer target to mimic the mRNA.
authors.affiliation: Department of Pathology, Uniformed Services University of the Health Science, Bethesda, Maryland 20814.
authors.forename: E H
authors.initials: EH
authors.lastname: Chang
authors.forename: Z
authors.initials: Z
authors.lastname: Yu
authors.forename: K
authors.initials: K
authors.lastname: Shinozuka
authors.forename: G
authors.initials: G
authors.lastname: Zon
authors.forename: W D
authors.initials: WD
authors.lastname: Wilson
authors.forename: A
authors.initials: A
authors.lastname: Strekowska
mesh_terms: D000818:Animals; D005786:Gene Expression Regulation / Q000187:drug effects; D066298:In Vitro Techniques; D051379:Mice; D008807:Mice, Inbred BALB C / Q000235:genetics; D009693:Nucleic Acid Hybridization; D009841:Oligonucleotides / Q000138:chemical synthesis / Q000494:pharmacology*; D016376:Oligonucleotides, Antisense; D015689:Oncogene Protein p21(ras) / Q000235:genetics*; D063065:Organophosphonates; D010957:Plasmids; D014176:Protein Biosynthesis / Q000187:drug effects; D013329:Structure-Activity Relationship; D013696:Temperature; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D009841:Oligonucleotides; D016376:Oligonucleotides, Antisense; D063065:Organophosphonates; D015689:Oncogene Protein p21(ras)