Mir137^tm1.2Mtm

A targeting vector was designed to insert an FRT site followed by a lacZ gene, a loxP site, a neomycin resistance gene cassette, a second FRT site and a second loxP site (FRT-lacZ-loxP-Neo-FRT-loxP) upstream of the microRNA stem loop and a third loxP site immediately downstream of the microRNA stem loop. The reporter and selection cassettes were deleted through flp-mediated recombination. This was intended to create a functional conditional-ready allele but the parent allele Mir137tm1Mtm, which was intended to be a reporter knockout allele, was shown to lack beta-galactosidase expression, suggesting that the inserted FRT and/or LoxP recombination sites interfere with the transcription of the allele. Consequently, this allele remains a null allele and did not turn into a conditional-ready allele. (J:244465)