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. 2011 Apr 27;2(4):273–281. doi: 10.1007/s13238-011-1037-y

Silencing suppressors: viral weapons for countering host cell defenses

Liping Song 1, Shijuan Gao 1, Wei Jiang 1, Shuai Chen 1, Yanjun Liu 3, Ling Zhou 3, Wenlin Huang 1,2,✉
PMCID: PMC4875207  PMID: 21528352

Abstract

RNA silencing is a conserved eukaryotic pathway involved in the suppression of gene expression via sequence-specific interactions that are mediated by 21-23 nt RNA molecules. During infection, RNAi can act as an innate immune system to defend against viruses. As a counter-defensive strategy, silencing suppressors are encoded by viruses to inhibit various stages of the silencing process. These suppressors are diverse in sequence and structure and act via different mechanisms. In this review, we discuss whether RNAi is a defensive strategy in mammalian host cells and whether silencing suppressors can be encoded by mammalian viruses. We also review the modes of action proposed for some silencing suppressors.

Keywords: RNA interference (RNAi), silencing suppressors, mammalian virus

Footnotes

These authors contributed equally to the work.

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