C57BL/6J-Grm3^tm1.1Conn/J

Stock number: 037935
Product name: Grm3^Fl
Research areas: Developmental Biology Research, Neurobiology Research, Research Tools

Description

Grm3^Fl floxed mice have loxP sites flanking exon 3 of the Grm3 gene. These mice may be useful when studying the role of mGlu₃ receptors in the regulation of synaptic plasticity and cognition.

Detailed description

Grm3^Fl floxed mice have loxP sites flanking exon 3 of the glutamate receptor, metabotropic 3 (Grm3) gene. Grm3 encodes the mGlu₃ subtype of the metabotropic glutamate receptor. Mutations in GRM3 have been associated with inpaired performance in memory-based tasks, cognitive deficits, and neuropsychiatric disorders such as schizophrenia. Mice that are homozygous for this allele are viable and fertile. When bred to mice that express tissue-specific cre recombinase, resulting offspring will have exon 3 removed in the cre-expressing tissues of the offspring.

When bred to CaMKII Cre mice (Stock No. 005359), expressing cre in the pyramidal cell layer in the cortex and hippocampus, resulting female Grm3-CaMKII KO offspring exhibit increased freezing relative to the control mice in a trace fear conditioning test, a high-demand associative learning task disrupted in patients with schizophrenia. Further, systemic administration of LY379268 (mGlu_2/3 receptor agonist) potentiated trace fear conditioning in littermate control mice with no difference in freezing observed between vehicle- and LY379268-treated male Grm3-CaMKII KO mice.

Development

The Grm3^Fl targeting vector was designed to insert a loxP site upstream of exon 3 of the glutamate receptor, metabotropic 3 (Grm3) gene, and a frt-flanked neomycin resistance cassette, followed by a second loxP site, was inserted downstream of exon 3. The construct was electroporated into C57BL/6J-derived FLP embryonic stem (ES) cells. Correctly targeted ES cells were injected into BALB/c blastocysts and resulting chimeric mice, lacking the neo cassette, were further bred to C57BL/6J mice (Stock No. 000664) for at least 5 generations by the donating laboratory. Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes.

Allele

Symbol: Grm3^tm1.1Conn
Name: targeted mutation 1.1, P Jeffery Conn
MGI accession ID: MGI:7411111
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed)
Synonyms: Grm3^Fl
Marker symbol: Grm3
Marker name: glutamate receptor, metabotropic 3
Marker synonyms: 0710001G23Rik; GLUR3; Gprc1c; mGlu3; MGLUR3
Chromosome: 5
Strain of origin: C57BL/6J
Molecular note: The targeting construct is designed to insert a loxP site upstream of exon 3 and a FRT-flanked neomycin resistance cassette, followed by a second loxP site, inserted downstream of exon 3. Flp-mediated recombination removed the neo cassette.
General note: ES cells = C57BL/6J-derived FLP embryonic stem cells