The invention relates to recombinant vectors for inducible and/or tissue
specific expression of double-stranded RNA molecules that interfere with
the expression of a target gene. In certain embodiments, the invention
relates to the use of Tet (tetracycline)-responsive RNA Polymerase II
(Pol II) promoters (e.g., TetON or TetOFF) to direct inducible knockdown
in certain cells of an integrated or an endogenous gene, such as p53. The
invention also relates to a method for producing transgenic animals
(e.g., mice) expressing inducible (such as tetracycline-regulated),
reversible, and/or tissue-specific double-stranded RNA molecules that
interfere with the expression of a target gene.