B6;129S1-Nodal^tm2Mku/J

Stock number: 021980
Research areas: Developmental Biology Research, Research Tools

Description

This floxed strain may be useful for studying axial patterning during development.

Detailed description

These Nodal^fl2 floxed mutant mice possess loxP sites flanking exons 2-3 of the Nodal gene. NODAL belongs to the Transforming Growth Factor beta (TGF-β) superfamily of secreted signaling molecules and plays a role in axial patterning and germ layer development during early vertebrate development. Mice that are homozygous for this allele are viable and fertile. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exons 2-3 deleted in cre-expressing tissues.

For example, when crossed to a strain expressing Cre recombinase in the mesodermal and definitive endodermal lineages, double mutant mice exhibit left/right axial defects.

Development

A targeting vector was designed to insert a single loxP site upstream of exon 2, and a loxP-flanked neomycin resistance (neo) cassette downstream of exon 3 of the Nodal gene. The construct was electroporated into 129S1/Sv-Oca2⁺ Tyr⁺ Kitl⁺-derived W9.5 embryonic stem (ES) cells. Correctly targeted ES cells were transiently transfected with a cre expression plasmid to delete the neo cassette. Resulting ES cells contained multiple gene rearrangments; intact floxed-exons 2-3, intact floxed-neo cassette, or excision of both exons 2-3 and the neo cassette. Correctly targeted ES cells, containing only the floxed-exons, were injected into blastocysts and resulting chimeric males were bred with C57BL/6 females. Resulting offspring were bred to establish a colony of Nodal^fl2 mice. Upon arrival, mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation.

Allele

Symbol: Nodal^tm2Mku
Name: targeted mutation 2, Michael R Kuehn
MGI accession ID: MGI:3830289
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Marker symbol: Nodal
Marker name: nodal
Chromosome: 10
Strain of origin: 129S1/Sv-Oca2⁺ Tyr⁺ Kitl⁺
Molecular note: A loxp site was inserted into intron 1 and a floxed PGK-neo cassette was inserted into the 3' UTR via homologous recombination. The PGK-neo cassette was then removed by in-vitro Cre-mediated recombination.