B6;129-Pitx2^tm1.1Sac/J

Stock number: 018120
Product name: Pitx2^flox
Research areas: Cardiovascular Research, Developmental Biology Research, Endocrine Deficiency Research, Internal/Organ Research, Neurobiology Research, Research Tools

Description

These Pitx2^flox mice are useful when studying heart, eye, and pituitary gland development.

Detailed description

These Pitx2^flox mice possess loxP sites flanking exon 4 of the paired-like homeodomain transcription factor 2 (Pitx2) gene. PITX2 is a transcription factor expressed in many tissues including the hypothalamus, eye, mandible, pituitary gland, and heart. PITX2 is involved in memory processing and regulating neural axonal migration. Mutations in PITX2 have been associated with Rieger syndrome, a haploinsufficiency disorder affecting the eyes and teeth. Homozygotes are viable, fertile, and normal in size. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exon 4 deleted in cre-expressing tissues.

For example, when bred to B6.Cg-Tg(Nes-cre)1Kln/J (Stock No. 003771) expressing Cre in the nervous system, the resulting offspring display an abnormal development of mammillothalamic tracts.

Development

A targeting vector was designed to insert a loxP-flanked neomycin resistance cassette, in opposite orientation to the gene (neoR), upstream of exon 4, and a single loxP site downstream of exon 4 of the paired-like homeodomain transcription factor 2 (Pitx2) gene. The construct was electroporated into (129X1/SvJ x 129S1/Sv)F1-Kitl<+>-derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were transiently transfected with a pMC-Cre expression plasmid to delete the neoR cassette. Resulting ES cells contained multiple gene rearrangments; intact floxed-exon 4, intact floxed-neoR cassette, or excision of both exon 4 and the neoR cassette. Correctly targeted ES cells, containing only the floxed-exon 4, were injected into C57BL/6J blastocysts and resulting chimeric males were bred with C57BL/6J females. Resulting offspring were bred to establish a colony of Pitx2^flox mice. These mice were backcrossed to C57BL/6J mice for an unknown number of generations prior to sending to The Jackson Laboratory Repository.

Allele

Symbol: Pitx2^tm1.1Sac
Name: targeted mutation 1.1, Sally A Camper
MGI accession ID: MGI:5298075
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Marker symbol: Pitx2
Marker name: paired-like homeodomain transcription factor 2
Chromosome: 3
Strain of origin: (129X1/SvJ x 129S1/Sv)F1-Kitl⁺
Molecular note: Gene targeting was performed with a vector engineered to contain a loxP site downstream from exon 4 and a floxed neomycin cassette upstream of exon 4. The floxed neo cassette was excised by transient cre expression leaving exon 4 flanked by loxP sites.