U6 promoter

The endogenous U6 promoter normally controls expression of the U6 RNA, a small nuclear RNA (snRNA) involved in splicing, and has been well-characterized (Kunkel et al., 1986; Kunkel and Pederson, 1988; Paule and White, 2000). This particular promoter was chosen to control vector-based expression of shRNA molecules in Mammalian cells (Paddison et al., 2002; Paul et al., 2002) for the following reasons: The promoter is recognized by RNA Polymerase III and controls high-level, constitutive expression of shRNA. The promoter is active in most mammalian cell types. The promoter is a type III Pol III promoter in that all elements required to control expression of the shRNA are located upstream of the transcription start site (Paule and White, 2000).