B6;129S1-Osr1^tm2.2Jian/Mmjax

Stock number: 039690
Product name: Osr1^c
Strain synonyms: Osr1^f
Research areas: Cell Biology Research, Developmental Biology Research, Internal/Organ Research, Research Tools

Description

Osr1^c mice possess loxP sites flanking exon 2 of Osr1 gene. These mice may be useful for generating conditional Osr1 mutants when studying the regulatory role of OSR1 in early heart and urogenital development.

Detailed description

Odd-skipped related transcription factor 1 (coded by Osr1) is essential in embryogenesis, specifically in developing heart and urogenital tissues. These Osr1^c mice carry loxP sites flanking exon 2 of the Osr1 gene. Mice homozygous for this floxed allele are viable and fertile. The donating laboratory indicates that some homozygous mice are significantly smaller than wildtype littermates on occasion. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have exon 2 deleted leading to ablation of OSR1 in cre-expressing tissues. These mice may be useful when studying early development of the heart and urogenital systems.

Development

The Osr1^c allele was generated using a targeting construct composed of an initial loxP site and an FRT-flanked neomycin cassette upstream of exon 2 of the odd-skipped related transcription factor 1 (Osr1) gene. A second loxP site was inserted into intron 2. The construct was electroporated into 129S1/Sv-Oca2⁺ Tyr⁺ Kitl+-derived CJ7 embryonic stem (ES) cells. Targeted ES cells were injected into C57BL/6J blastocysts. The resulting chimeric mice were bred with C57BL/6J mice to establish germline transmission. The FRT-flanked neomycin cassette was subsequently removed by crossing to a ROSA26::FLPe knock-in mouse line, on a C57BL/6 background. The FLP-expressing transgene was then removed through selective breeding. The resulting Osr1^c mice, with neo cassette removed and floxed exon 2 intact, were further backcrossed on to the C57BL/6J background for at least 2 generations by the donating laboratory. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes.

Allele

Symbol: Osr1^tm2.2Jian
Name: targeted mutation 2.2, Rulang Jiang
MGI accession ID: MGI:5004961
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Synonyms: Osr1^f
Marker symbol: Osr1
Marker name: odd-skipped related transcription factor 1
Marker synonyms: ODD; Odd1
Chromosome: 12
Strain of origin: 129S1/Sv-Oca2⁺ Tyr⁺ Kitl⁺
Molecular note: Flp-mediated recombination removed the neo cassette. Exon 2 remains floxed.