B6;129S7-Drd2^tm1.1Jtw/J

Stock number: 030537
Product name: GFP-D2
Research areas: Neurobiology Research, Research Tools

Description

GFP-D2 knock-in mice express a mouse DRD2 (dopamine receptor D2)-superecliptic pHluorin (SpH) fusion protein. The pH-sensitive GFP tag is useful in tagging dopamine D2 receptors that retain normal function. This strain enables the detection of exocytosis and endocytosis of synaptic vesicles.

Detailed description

Dopamine D2 receptors are crucial for many behavioral processes and a number of disease states including Parkinson's disease, drug addiction, and schizophrenia.

These GFP-D2 knock-in mice express a mouse DRD2 (dopamine receptor D2)-superecliptic pHluorin (SpH) fusion protein useful in tagging dopamine D2 receptors that retain normal function. SpH is a pH-sensitive GFP variation that enables the detection of exocytosis and endocytosis of synaptic vesicles. The SpH-tagged receptor functions normally, as measured by the ability to activate a G protein-coupled inwardly rectifying potassium (GIRK) conductance.

Immunohistochemistry is needed to detect SpH. Anti-GFP antibodies are effective and staining is best when done in living tissue. Staining in tissue from perfused mice is poor.

This strain has been used to examine the distribution and functional consequences of D2 autoreceptor activation in live neurons from the SNc (substantia nigra pars compacta). GFP-tagged D2 receptors are unevenly distributed into clusters or puncta on the cell membrane of the soma to the distal dendrites of dopamine neurons within the SNc. Experiments suggest that D2 receptors are not internalized with prolonged agonist activation.

Development

A superecliptic pHluorin (SpH) with a human prolactin hormone signal sequence was introduced to exon 2 of the mouse Drd2 gene, enabling the expression of a fused GFP-D2R protein. A loxP-flanked PGK-neomycin cassette was placed in intron 2. The knock-in mutation was created via homologous recombination in C57BL/6N-derived JM8.N4 embryonic stem (ES) cells. Resultant mice were crossed with C57BL/6N-HPRT^{tm1(CMV-cre)Brd}/MMucd mice to excise the neomycin cassette. This strain was maintained on a C57BL/6N genetic background by the donating laboratory.

Allele

Symbol: Drd2^tm1.1Jtw
Name: targeted mutation tm1.1, John Williams
MGI accession ID: MGI:6406268
Generation method: Targeted
Attributes: Reporter
Synonyms: GFP-D2
Marker symbol: Drd2
Marker name: dopamine receptor D2
Marker synonyms: D2 receptor; D2DR; D2R; Drd-2
Chromosome: 9
Strain of origin: C57BL/6N
Site of expression: DRD2-expressing cells/tissues

Molecular note: A superecliptic pHluorin (SpH) with a human prolactin hormone signal sequence was introduced to exon 2 of the mouse Drd2 gene, enabling the expression of a fused GFP-D2R protein. A loxP-flanked PGK-neomycin cassette was placed in intron 2. Cre-mediated recombination removed the floxed neo cassette.