Mir137^tm1Mtm

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. This was intended to create a knockout-first conditional-ready reporter knockout allele, but no beta-galactosidase activity could be detected in adult or embryonic tissues of heterozygous mice, nor could a functional conditional-ready allele be created after flp-mediated deletion of the insert, suggesting that the inserted FRT and/or LoxP recombination sites interfere with the transcription of the allele. (J:181752, J:244465)