Flox-EAAT2 mice possess loxP sites flanking exons 3 and 4 of the Slc1a2 gene. This strain may be useful for generating conditional mutations in applications related to the regulation of excitatory glutamate neurotransmission, and the glutamate-glutamine cycle.
Niels Christian Danbolt, University of Oslo
The Slc1a2 gene encodes an excitatory glutamate transporter (EAAT2;
GLT-1) that is responsible for almost all of the total glutamate uptake activity in the forebrain. EAAT2 removes glutamate from the extracellular spaces (both inside and outside of the synapses) and thereby protects neurons against harmful activation of glutamate receptors. Perturbations in EAAT2 functioning have been associated with a number of neurological disorders including amyotrophic lateral sclerosis. In the brain, EAAT2 is predominantly expressed on astrocytes, but is also found on axon-terminals.
These mice possess loxP sites on either side of exons 3 and 4 of the targeted gene. 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 exons 3 and 4 deleted in the cre-expressing tissues.
When bred to a strain with Cre recombinase expression in developing neuronal tissues (see Stock No. 003771 for example), the resulting mutant mice exhibit spontaneous seizures, hyperactivity and premature death.
A targeting vector containing FRT site flanked PGK-Neo selection cassette was utilized in the construction of this mutant. This selection cassette was inserted downstream of exon 4 of the targeted gene, and another loxP site was inserted upstream of exon 2. This construct was electroporated into (129S6/SvEvTac x C57BL/6J)F1 derived D1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts. Chimeric mice were generated by aggregating correctly targeted ES cells with CD-1 eight-cell embryos. The resulting chimeric animals were crossed to mice expressing FLP recombinase (Stock No. 003946). Mice that retained the loxP site flanked exons 3 and 4 were then bred to C57BL/6J mice to remove the FLP1 recombinase allele. The mice were backcrossed to C57BL/6J for 22 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 Name||targeted mutation 1.1, NC Danbolt|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Slc1a2, solute carrier family 1 (glial high affinity glutamate transporter), member 2|
|Strain of Origin||(129S6/SvEvTac x C57BL/6J)F1|
|Molecular Note||A loxP site was inserted into intron 2 and an frt-neo-frt-loxP cassette was inserted into intron 4, floxing exons 3 and 4 of the Slc1a2 gene from the bacterial artificial chromosome clone RP24-315H4. The neomycin cassette was removed via FLP-mediated recombination, leaving exons 3 and 4 floxed by loxP sites. Cre-mediated recombination can be used to remove exons 3 and 4 which results in a frameshift deletion.|
When maintaining a live colony, these mice can be bred as homozygotes.
When using the Flox-EAAT2 , Flox-GLT-1 mouse strain in a publication, please cite the originating article(s) and include JAX stock #026619 in your Materials and Methods section.