Patent ID: 6995011

Claim:
A single vector comprising a gene arrangement satisfying all of the following requirements (1) to (4) when inserted into the genome of a mammalian cell: (1) a DNA encoding a low molecular weight compound-controlled transactivator placed on one side of a bidirectional promoter responsive to said low molecular weight compound, and a DNA encoding a site-specific recombinase and a polyadenylation signal sequence placed on the other side of said promoter, wherein said low molecular weight compound is at least one selected from the group consisting of tetracycline, doxycycline, FK506, RU486, ecdysone and streptogramin; (2) a gene of interest placed between two target sites of said site-specific recombinase; (3) the gene of interest placed under the control of a promoter capable of directing expression of said gene in mammalian cells, and the DNA encoding said site-specific recombinase placed in such a manner that a transcript from said promoter includes a transcript of the site-specific recombinase DNA, and that the latter transcript and another transcript of the site-specific recombinase DNA from the bidirectional promoter of (1) form a double-stranded RNA; (4) polyadenylation signal sequences which are capable of adding poly(A) to a transcript of the low molecular weight compound-controlled transactivator and a transcript from the promoter capable of directing expression in mammalian cells, respectively.