Transgenerational functions of small RNA pathways in controlling gene expression in C. elegans

Abstract

RNA silencing processes use exogenous or endogenous RNA molecules to specifically and robustly regulate gene expression. In C. elegans, initial mechanistic descriptions of the different silencing processes focused on posttranscriptional regulation. In this review, we discuss recent work showing that, in this model organism, RNA silencing also controls the transcription of target genes by inducing heterochromatin formation. Specifically, it has been shown that ribonucleoprotein complexes containing small RNAs, either processed from exogenous dsRNA or synthesized from the genome itself, and proteins of the Argonaute family, mediate the deposition of repressive histone marks at the targeted loci. Interestingly, the accumulation of repressive marks is required for the inheritance of the silencing effect and the establishment of an epigenetic memory that discriminates self- from non-self-RNAs.

Keywords: :

• C. elegans
• RNA interference
• RNA-induced epigenetic silencing
• histone modifications
• small RNAs
• transgenerational gene silencing

10.4161/epi.26795

Disclosure of Potential Conflicts of Interest

No potential conflicts of interest were disclosed.

Acknowledgments

Authors thank Anne Laurençon-Loviton and Steve Garvis for the careful reading of the manuscript. Research in the laboratory of F. Palladino is funded by the Association pour la Recherche contre le Cancer, the Ligue Contre le Cancer, the Centre Nationale de la Recherche Scientifique (CNRS) and the Agence Nationale pour la Recherche.