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A cytoplasmic pathway for gapmer antisense oligonucleotide-mediated gene silencing in mammalian cells.

ABSTRACT: Antisense oligonucleotides (ASOs) are known to trigger mRNA degradation in the nucleus via an RNase H-dependent mechanism. We have now identified a putative cytoplasmic mechanism through which ASO gapmers silence their targets when transfected or delivered gymnotically (i.e. in the absence of any transfection reagent). We have shown that the ASO gapmers can interact with the Ago-2 PAZ domain and can localize into GW-182 mRNA-degradation bodies (GW-bodies). The degradation products of the targeted mRNA, however, are not generated by Ago-2-directed cleavage. The apparent identification of a cytoplasmic pathway complements the previously known nuclear activity of ASOs and concurrently suggests that nuclear localization is not an absolute requirement for gene silencing.

SUBMITTER: Castanotto D

PROVIDER: S-EPMC4627093 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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A cytoplasmic pathway for gapmer antisense oligonucleotide-mediated gene silencing in mammalian cells.

Castanotto Daniela D Lin Min M Kowolik Claudia C Wang LiAnn L Ren Xiao-Qin XQ Soifer Harris S HS Koch Troels T Hansen Bo Rode BR Oerum Henrik H Armstrong Brian B Wang Zhigang Z Bauer Paul P Rossi John J Stein C A CA

Nucleic acids research 20151003 19

Antisense oligonucleotides (ASOs) are known to trigger mRNA degradation in the nucleus via an RNase H-dependent mechanism. We have now identified a putative cytoplasmic mechanism through which ASO gapmers silence their targets when transfected or delivered gymnotically (i.e. in the absence of any transfection reagent). We have shown that the ASO gapmers can interact with the Ago-2 PAZ domain and can localize into GW-182 mRNA-degradation bodies (GW-bodies). The degradation products of the targete ...[more]

PMID: 26433227

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