STOCK Bmi1^tm1.1Lees/J

Stock number: 028572
Product name: Bmi1^fl
Research areas: Research Tools

Description

Bmi1 is upregulated in a progressive manner in a wide variety of human tumors. Exons 4-8 of the mouse Bmi1 gene are flanked by loxP sites in this targeted allele. Cre-mediated excision of the floxed region results in a null allele.

Detailed description

Bmi1 (Bmi1 polycomb ring finger oncogene) is a key transcriptional regulator in several organ stem cells and in cancer. Expression is upregulated in a progressive manner in a wide variety of human tumors, including colorectal cancer.

Exons 4-8 of the mouse Bmi1 gene are flanked by loxP sites in this targeted allele. Cre-mediated excision of the floxed region results in a null allele.

In a study of intestinal tumorigenesis, a conditional knockout of the Apc gene (Apc;Vil-cre) was combined with a germline knockout of Bmi1. In contrast to wild-type controls, compound mutant mice showed no increase in median tumor size, and a dramatic decrease in tumor number, between 3 and 4 months of age. As such, it is believed that the gene is required for both progression and maintenance of small intestinal adenomas.

Development

An FRT-flanked neomycin resistance cassette was placed in intron 3, upstream of loxP sites inserted in introns 3 and 8. The mutation was created via homologous recombination in (C57BL/6 x 129S4/SvJae)F1-derived v6.5 embryonic stem (ES) cells. The selection cassette was subsequently deleted from resultant mice through crosses with a β-actin FLP mouse strain, leaving exons 4-8 were flanked by loxP sites. This strain was maintained on a mixed genetic background (involving 129S4/SvJae and C57BL/6, and possibly others) by the donating laboratory.

Allele

Symbol: Bmi1^tm1.1Lees
Name: targeted mutation 1.1, Jacqueline A Lees
MGI accession ID: MGI:5532395
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Marker symbol: Bmi1
Marker name: Bmi1 polycomb ring finger oncogene
Chromosome: 2
Strain of origin: (C57BL/6 x 129S4/SvJae)F1
Molecular note: An FRT flanked neo cassette was inserted in intron 3 upstream of loxP sites inserted in intron 3 and in intron 8. The selection cassette was subsequently deleted by crossing to a b-actin FLP mouse strain. Exons 4 to 8 were thus flanked by loxP sites.