B6.Cg-Axin2^tm1.1Rva/J

Stock number: 036013
Product name: Axin2^{P2A-rtTA3-T2A-3xNLS-SGFP2}
Research areas: Cell Biology Research, Research Tools

Description

Axin2^{P2A-rtTA3-T2A-3xNLS-SGFP2} knockin mice express a doxycycline-inducible reverse tetracycline transactivator (rtTA3) and an SGFP2 (strongly enhanced green fluorescent protein) reporter without affecting Axin2 expression. These mice may be useful as a reporter for WNT/CTNNB1 signaling as well as a lineage tracing driver for WNT/CTNNB1 responsive stem cells.

Detailed description

Axin2 (axin 2) encodes a negative feedback regulator protein involved in the stabilization of β-catenin in the WNT/CTNNB1 (β-catenin) signaling pathway. WNT/CTNNB1 signaling is critical to embryonic development and is involved in the regulation of stem cell maintenance and homeostasis in adult tissues. Axin2^{P2A-rtTA3-T2A-3xNLS-SGFP2} knockin mice express a doxycycline-inducible reverse tetracycline transactivator (rtTA3) and an SGFP2 (strongly enhanced green fluorescent protein) reporter fused with a nuclear localization sequence inserted at the Axin2 stop codon in 3’ UTR. The insertion does not affect the expression of Axin2. Axin2^{P2A-rtTA3-T2A-3xNLS-SGFP2} mice can be used to label WNT/CTNNB1 responsive cells at multiple sites during different stages of embryonic and postnatal development. Mice homozygous for the mutation are viable and fertile with no obvious phenotype. These mice may be useful as a reporter for WNT/CTNNB1 signaling as well as a lineage tracing driver for WNT/CTNNB1 responsive stem cells.

Development

The targeting construct contains a P2A, a reverse tetracycline transactivator (rtTA3), a T2A, an SGFP2 (strongly enhanced green fluorescent protein) with a 3XNLS (nuclear localization signal) followed by an FRT-flanked PGK neo cassette (in reverse orientation) inserted at the stop codon (TGA) in exon 11 of the Axin2 locus. The remaining Axin2 coding sequence including all intron/exon boundaries and all regulatory 5' and 3' sequences are intact and AXIN2 protein expression is preserved. The construct was electroporated into B6.Cg-Thy1^a-derived Bruce4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric males were crossed to females carrying a Gt(ROSA)26Sor^{tm1.1(UBC-flpe)Ozg}(OzFlp) on a C57BL/6 background to remove the neomycin cassette. The strain was maintained on the C57BL/6JRccHSd background. Upon arrival, mice were bred to C57BL/6J for at least one generation to establish the colony, and then the strain was cryopreserved.

Allele

Symbol: Axin2^tm1.1Rva
Name: targeted mutation 1.1, Renee van Amerongen
MGI accession ID: MGI:6360044
Generation method: Targeted
Attributes: Reporter; Transactivator
Synonyms: Axin2 P2A-rtTA3-T2A-3xNLS-sGFP2
Marker symbol: Axin2
Marker name: axin 2
Marker synonyms: Axil; axin-2; Conductin; ODCRCS
Chromosome: 11
Strain of origin: B6.Cg-Thy1^a
Site of expression: Axin2-expressing cells

Molecular note: The targeting construct contains a P2A, a reverse tetracycline transactivator (rtTA3), a T2A, an SGFP2 (strongly enhanced green fluorescent protein) with a 3XNLS (nuclear localization signal) followed by an FRT-flanked PGK neo cassette (in reverse orientation) inserted at the stop codon (TGA) in exon 11. Flp-mediated recombination removed the FRT-flanked neo cassette.