B6.129S6(Cg)-Nkx2-2^{tm4.1(cre/EGFP)Suss}/J

Stock number: 026880
Product name: Nkx2-2:Cre-EGFP
Research areas: Developmental Biology Research, Neurobiology Research, Research Tools

Description

These Nkx2-2:Cre-EGFP Knockin/knockout mice may have applications in studies requiring conditional gene manipulation or lineage fate mapping in the CNS, pancreas and intestine.

Detailed description

The Nkx2-2 gene encodes for a transcriptional activator that is involved in cell differentiation in the CNS, pancreas and intestine. These transgenic mice express a cre/EGFP fusion gene driven by the mouse Nkx2-2 promoter. The cre/EGFP was fused in-frame with the ATG start codon, most of exon 1 is deleted. Transgene expression and high levels of Cre recombinase activity are detected in Nkx2-2-expressing cells. Low levels of EGFP are detected by direct fluorescence and FACS. The homozygous mice are neonatal lethal due to pancreas and CNS defects. Heterozygotes are viable and fertile.

Development

A targeting vector containing a cre/EGFP fusion gene and a FRT site flanked hygromycin cassette downstream was inserted into Nkx2-2^tm1Suss (Nkx2-2^LCA) by recombinase mediated cassette exchange (RMCE) fusing the cre/EGFP fusion gene in-frame with the ATG start codon, replacing all but 25 base pairs of the first coding exon. This vector was co-injected with a cre recombinase expression vector into 129S6/SvEvTac derived TL1 ES cells containing an Nkx2-2 (loxed cassette acceptor) allele. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric animals were bred to C57BL/6J mice. The mice were bred to ACTB-Flpe mice (on a mixed background) to excise the FRT flanked hygromycin cassette, and then backcrossed to C57BL/6J for more than 20 generations. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) at least once to establish the colony.

Allele

Symbol: Nkx2-2^{tm4.1(cre/EGFP)Suss}
Name: targeted mutation 4.1, Lori Sussel
MGI accession ID: MGI:5538250
Generation method: Targeted
Attributes: Recombinase-expressing; Null/Knockout
Marker symbol: Nkx2-2
Marker name: NK2 homeobox 2
Chromosome: 2
Strain of origin: 129S6/SvEvTac
Expressed genes: GFP/cre,Green Fluorescent Protein/Cre recombinase fusion protein,
Site of expression: Cre recombinase and EGFP are expressed in Nkx2-2-expressing cells of the central nervous system, pancreas, and intestine.
Molecular note: A cre/EGFP fusion gene and Frt-flanked hygro selection cassette were inserted using recombineering into an Nkx2-2 basal exchange vector such that cre/EGFP was fused in-frame with the ATG start codon, replacing all but 25 base pairs of the first coding exon. This vector was co-injected with a cre-expression vector into ES cells containing an Nkx2-2 (loxed cassette acceptor) allele. Correctly exchanged ES clones were used to produce chimeras which were bred to B6 mice to verify germline transmission. Animals were bred to ACTB-Flpe mice to excise the hygromycin marker.