STOCK Isl1^tm1(cre)Sev/J

Stock number: 024242
Product name: Isl1Cre
Research areas: Cardiovascular Research, Developmental Biology Research, Neurobiology Research, Research Tools

Description

Isl1Cre mice express Cre recombinase under the control of the ISL1 transcription factor, LIM/homeodomain promoter and are an effective tool for studying heart and limb abnormalities.

Detailed description

Isl1Cre mice express Cre recombinase under the control of the endogenous ISL1 transcription factor, LIM/homeodomain (Isl1) promoter. ISL1 is expressed in undifferentiated cardiac progenitors and hindlimb progenitors. Expression in both locations is downregulated as these cells migrate into the heart or limb, respectively. Isl1 expression is ablolished in this strain. When crossed with a strain containing a loxP site-flanked sequence, Cre-mediated recombination results in deletion of the flanked sequence in cardiac and hindlimb progenitor cells. Heterozygotes are viable and fertile, homozygotes are embryonic lethal.

For example, when bred to mice expressing a floxed version of the bone morphogenetic protein receptor, type 1A (Bmpr1a), lack of BMP signaling in cardiac and hindlimb progenitor cells leads to complete neonatal lethality by E14.5, due to abnormal fetal cardiomyocyte development and persistent truncus arteriosis. These mice also exhibited smaller hindlimb buds and abnormal hindlimb formation.

Development

A targeting vector was designed to insert a Cre recombinase gene, followed by a frt-flanked neo cassette, 6 bp upstream of the translation initiation codon of the ISL1 transcription factor, LIM/homeodomain (Isl1) gene. The construct was electroporated into 129S embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts and resulting chimeric mice were bred to Black Swiss outbred mice. Upon arrival at The Jackson Laboratory, mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.

Allele

Symbol: Isl1^tm1(cre)Sev
Name: targeted mutation 1, Sylvia Evans
MGI accession ID: MGI:3623159
Generation method: Targeted
Attributes: Recombinase-expressing
Marker symbol: Isl1
Marker name: ISL1 transcription factor, LIM/homeodomain
Chromosome: 13
Strain of origin: 129S/Sv
Expressed genes: cre,cre recombinase,bacteriophage P1
Site of expression: When mice carrying this allele are crossed with a strain containing a loxP site-flanked sequence, Cre-mediated recombination results in deletion of the flanked sequence in cardiac and hindlimb progenitor cells.
Molecular note: A cre gene and frt-flanked neo cassette were inserted 6 bp upstream of the translation initiation codon. The neo cassette was removed by germ line, flp-mediated recombination. Expression of cre is regulated by the endogenous promoter.