B6(129S4)-Mirc32^tm1.1Tyj/J

Stock number: 021213
Research areas: Research Tools

Description

Mir143 (microRNA 143) and Mir145 (microRNA 145) are flanked by loxP sites in this targeted mutation strain, enabling the generation of Cre-mediated, tissue-specific knockouts that affect smooth muscle function.

Detailed description

The mir-143~145 cluster on mouse Chromosome 18 encodes two unrelated miRNAs, Mir143 (microRNA 143) and Mir145 (microRNA 145). Germline deletion of the cluster leads to a range of smooth muscle-related phenotypes (including megacolon, vascular defects and male infertility) that occur with high penetrance and progress with aging.

Mir143 and Mir145 are flanked by loxP sites in this targeted mutation strain, thus enabling Cre-mediated recombination and excision of the cluster. In the floxed configuration, miRNA expression is not affected. Homozygotes are viable, fertile, and do not exhibit any overt phenotypes.

Development

LoxP sites were introduced approximately 250 bp 5' of Mir145 and 500 bp 3' of Mir143. A FRT-Neo-FRT cassette was also placed 3' of Mir143, just inside the floxed region. The mutation was created in (C57BL/6 x 129S4/SvJae)F1-derived v6.5 embryonic stem (ES) cells. The neomycin cassette was removed by breeding founders to a C57BL/6 background beta-actin FlpO strain. This strain was made congenic with C57BL/6 using speed congenic methods by the donating laboratory.

Allele

Symbol: Mirc32^tm1.1Tyj
Name: targeted mutation 1.1, Tyler Jacks
MGI accession ID: MGI:5447364
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Mirc32
Marker name: microRNA cluster 32, including Mir143 and Mir145a
Chromosome: 18
Strain of origin: (C57BL/6 x 129S4/SvJae)F1
Molecular note: LoxP sites were introduced approximately 250 bp 5' of Mir145 and 500 bp 3' of Mir143. A FRT-Neo-FRT cassette was also placed 3' of Mir143, just inside the floxed region. Flp-mediated recombination removed the neo cassette.