Generation of an inducible mouse ES cell lines deficient for Argonaute proteins.

Argonautes (Agos) are core effectors of RNA silencing. In several nonmammalian organisms, multiple Agos are known to exhibit specialized functions for distinct RNA silencing pathway. Mammals have four closely related Agos. To examine the functions of mammalian Agos in the microRNA silencing pathway, we generated mouse embryonic stem (ES) cells that are nullizygous for all Agos. This chapter describes a variety of techniques including BAC recombineering, gene targeting, and inducible Cre-loxP recombination, used to generate inducible Ago knock-out ES cells. The Ago-deficient ES cells provide an important tool for the study of mammalian RNA silencing.