Efficient Gene Knockdowns in Mouse Embryonic Stem Cells Using MicroRNA-Based shRNAs.

RNA interference (RNAi) is a powerful gene knockdown technology that has been applied for functional genetic loss-of-function studies in many model eukaryotic systems, including embryonic stem cells (ESCs). Application of RNAi in ESCs allows for dissection of mechanisms by which ESCs self-renew and maintain pluripotency and also for specifying particular cell types needed for cell replacement therapies. Potent RNAi response can be induced by expression of a microRNA-embedded short-hairpin RNA (shRNAmir) cassette that is integrated in the genome by virus infection or site-specific recombination at a defined locus. In this chapter, I will provide detailed protocols to perform shRNAmir-mediated RNAi studies in mouse ESCs using retrovirus infection and loxP site-directed recombination for efficient constitutive and inducible gene knockdown, respectively.