Kcnn2^tm2Jpad

A genetic switch based on the tetracycline transactivator/tetracycline operator (tTA/tetO) system was inserted into the 5' untranslated region (5' UTR) of the targeted gene 40 nucleotides upstream of the initiator ATG. The switch, after in vivo excision of a selection cassette, comprises a tripartite adenovirus leader sequence (to enhance translation initiation efficiency) followed by the coding sequence for the tTA protein with SV40 and human growth hormone polyadenylation signals separated by a single loxP site; and five copies of the tetracycline operator (tetO), also called the tetracycline responsive element (TRE), joined to the cytomegalovirus (CMV) minimal promoter. In the absence of doxycycline (Dox), heterozygous mutant mice express 4.5-fold the wild-type level of Kcnn2 mRNA and 10-fold the wild-type level of Kcnn2 subunit protein, respectively assessed by quantitative and real-time PCR of whole-brain RNA and by immunoblot analysis of membrane proteins from whole brains. Administration of Dox reduces, but does not eliminate, expression from the mutant allele. (J:95064, J:105645)