Rate of degradation of [alpha]- and [beta]-oligodeoxynucleotides in Xenopus oocytes. Implications for anti-messenger strategies.
End-labelled oligodeoxynucleotides were injected into Xenopus laevis oocytes and their degradation products were analysed by high-performance ion-exchange liquid chromatography after various times of incubation. The oligonucleotides were synthesised with either the natural [beta] anomers or the synthetic [alpha] anomers of deoxynucleotide units. Oligo-[beta] deoxynucleotides are short-lived inside oocytes (half-life approximately equal to 10 min). Covalent attachment of an intercalating agent to the 3'-phosphate and of a methylthiophosphate group at the 5'-end protects oligodeoxynucleotides against 3'- and 5'-exonucleases, respectively. The half-life of such substituted oligodeoxynucleotides is increased to 40 minutes. Oligo-[alpha]-deoxynucleotides are quite resistant to both endo and exonucleases inside Xenopus oocytes. After 8 hours only 40% of a 16-mer oligo-[alpha]-deoxynucleotide were hydrolysed. The rapid degradation of oligo-[beta]-deoxynucleotides suggests that efficient inhibition of translation in Xenopus oocytes involves an RNase H-induced hydrolysis of mRNAs hybridized to oligo-[beta]-deoxynucleotides.
D000166:Acridines; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D008845:Microinjections; D009838:Oligodeoxyribonucleotides / Q000378:metabolism*; D009865:Oocytes / Q000378:metabolism*; D012313:RNA / Q000378:metabolism; D016372:RNA, Antisense; D013997:Time Factors; D014982:Xenopus laevis
D000166:Acridines; D009838:Oligodeoxyribonucleotides; D016372:RNA, Antisense; D012313:RNA