STOCK Smad2^tm1.1Epb/J

Stock number: 022074
Product name: Smad2^f
Research areas: Cell Biology Research, Research Tools

Description

These Smad2^f/f mice possess loxP sites flanking exon 2 of the SMAD family member 2 gene. These mice may be useful for studying the cellular and mechanical role of TGF-β in regulating development.

Detailed description

These Smad2^f/f mice possess loxP sites flanking exon 2 of the SMAD family member 2 (Smad2) gene. SMAD2 is an intracellular signaling mediators involved in growth control and transcriptional regulation during development by transmitting chemical signals from the cell surface to the nucleus via the transforming growth factor β (TGFβ) signaling system. 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 exon 2 deleted in cre-expressing tissues.

For example, when crossed to B6.Cg-Tg(Cdh16-cre)91Igr/J mice (Stock No. 012237) expressing Cre recombinase in the kidney, TGF-β signaling is enhanced which promotes increased fibrosis.

When crossed to B6.Cg-Tg(Alb-cre)21Mgn/J mice (Stock No. 003574) expressing Cre recombinase in the liver, hepatocytes exhbit altered growth and dedifferentiation independent of TGF-beta signaling.

Development

A targeting vector was designed to insert a loxP-flanked neomycin resistance (neo) cassette upstream of exon 2, and a single loxP site downstream of exon 2 of the SMAD family member 2 (Smad2) gene. The construct was electroporated into STOCK (129/Sv and C57BL/6J and SJL)-derived WW6 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts and resulting chimeric males were bred with C57BL/6 x 129V females. Offspring were bred with CMV-cre transgenic mice to delete the neo cassette. Resulting progeny contained multiple gene rearrangments; intact floxed-exon 2, intact floxed-neo cassette, or excision of both exon 4 and the neo cassette. Mice, containing only the floxed-exon 2, were bred with C57BL/6J mice. Upon arrival, Smad2^f/f mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.

Allele

Symbol: Smad2^tm1.1Epb
Name: targeted mutation 1.1, Erwin P Bottinger
MGI accession ID: MGI:3703160
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Marker symbol: Smad2
Marker name: SMAD family member 2
Chromosome: 18
Strain of origin: STOCK 129/Sv and C57BL/6J and SJL
Molecular note: Exon 2, which contains the ATG, remained flanked by loxP sites following in vivo cre-mediated recombination by crossing floxed mice with cre mice. A floxed pgk-neomycin resistance cassette was removed from the locus.