Cell-free microRNA-mediated translation repression in Caenorhabditis elegans

In vitro recapitulation has recently led to significant advances in the understanding of the molecular functions of microRNAs. Cell-free systems allow a direct perspective on the different steps involved, and provide the experimenter with the opportunity to directly interfere with, or alter the implicated factors. In this chapter, we describe a cell-free translation system based on Caenorhabditis elegans embryo, which faithfully recapitulates miRNA-mediated translation repression. Because of the genetic and transgenic flexibility of this animal model, such a system provides a unique experimental resource to study the mechanism and the functions of miRNAs, the Argonautes, and the RISC.