B6;129S2-Emx1^tm1(cre)Yql/Mmjax

Stock number: 040994
Product name: Emx1-cre knock-in

Research areas: Neurobiology Research, Research Tools

Description

Emx1-cre knock-in mice express a nuclear-localized lacZ reporter and Cre recombinase from the mouse Emx (empty spiracles homeobox) promoter. Activity is reported to be consistent with known patterns of Emx1 expression. Protein expression of the targeted Emx1 gene is knocked out.

Detailed description

Emx1-cre knock-inmice express a nuclear-localized lacZ reporter and Cre recombinase from the mouse Emx (empty spiracles homeobox) promoter. Activity is reported to be consistent with known patterns of Emx1 expression.

LacZ staining of E12.5 embryos shows blue staining of neural cells restricted to the developing cerebral cortex. The only non-neural expression detected in the E12.5 embryos is localized to the developing limbs, consistent with published immunohistochemical studies. LacZ staining can be observed in nearly every neuron of the cerebral cortex and hippocampus from postnatal day 18 (P18) in heterozygous mice. Neurons are also stained in the olfactory bulb and amygdala. Protein expression of the targeted Emx1 gene is knocked out.

Development

A nuclear-localized lacZ-IRES-Cre-polyA-PGKneo cassette was introduced to exon 1 of the mouse Emx1 gene in 129S2/SvPas-derived D3 embryonic stem (ES) cells. This resulted in the deletion of an 18-bp NotI–SacII fragment encoding the first 4 amino acids of the EMX1 protein. Mice were backcrossed to C57BL/6J for one generation by the donating laboratory. Upon arrival, sperm was cryopreserved. To establish a live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

Allele

Symbol: Emx1^tm1(cre)Yql
Name: targeted mutation 1, Yuqing Li
MGI accession ID: MGI:2176219
Generation method: Targeted
Attributes: Recombinase-expressing
Synonyms: Emx1-cre
Marker symbol: Emx1
Marker name: empty spiracles homeobox 1
Marker synonyms: RGD1564002
Chromosome: 6
Strain of origin: 129S2/SvPas
Molecular note: A knock-in strategy was used to express cre in an EMX1- specific manner. A lacZ-IRES-cre cassette replaced a segment of the gene containing the first four amino acids of the encoded protein. This allele expresses a bicistronic mRNA encoding beta-galactosidase and Cre recombinase. The endogenous promotor is active in the cerebral cortex and hippocampus.
General note:

Three different lines of reporter mice show that Cre activity was restricted to the cerebral cortex and hippocampus, and occurred in 91% of the neurons in the cerebral cortex.