B6.Cg-Npy1r^{tm1.1(cre/GFP)Rpa}/J

Stock number: 030544
Product name: Npy1r^cre:GFP
Research areas: Neurobiology Research, Research Tools

Description

These targeted mutant mice express cre recombinase from the mouse Npyr1 (neuropeptide Y receptor Y1) promoter and have been useful in tracing synaptic networks.

Detailed description

Postsynaptic targets of hypothalamic NPY-expressing Agrp⁺ neurons express Npyr1 (neuropeptide Y receptor Y1). These mutant mice, expressing cre recombinase from the Npy1r promoter, are useful in defining the synapatic network originating from a subset of Agrp⁺ neurons.

When crossed with mice expressing a floxed stop tdTomato reporter (R26^fs-tdT/+; see Stock No. 007914), cre expression is detected in the anterior-dorsal, anterior ventral, posterior dorsal and posterior ventral medial amygdala (MeA). Injections of cre-dependent adeno-associated virus (AAV) fluorescent reporter are also effective in labeling cells.

A nuclear localizing signal (NLS) directs expression of cre to the nucleus. A Myc-tag feature has not been tested. Although incorporated in the targeting construct, GFP fluorescence is too low to be visualized directly or through immunohistochemistry.

Heterozygous and homozygous mice involving this mutation are viable, fertile, and show no overt phenotype as the coding region of the gene is unaffected. Expression levels of Npy1r have not been examined.

Development

The following were introduced just before the initiation codon of the mouse Npyr1 gene: Myc tag-nuclear localization signal (NLS)-Cre-GFP-frt-neomycin-frt. The mutation was created via homologous recombination in (129S6/SvEvTac x C57BL/6)F1-derived G4 embryonic stem (ES) cells. The frt-flanked neomycin cassette was excised through crosses with a Gt(ROSA)26Sor-Flp strain. Resultant mice were backcrossed to C57BL/6J for 9 generations by the donating laboratory (see SNP note below).



A 48 SNP (single nucleotide polymorphism) panel analysis, with 43 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6J and C57BL/6N substrains, was performed on the rederived living colony at The Jackson Laboratory Repository. While the 43 markers throughout the genome suggested a C57BL/6 genetic background, 1 of the 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6N;C57BL/6J genetic background.

Allele

Symbol: Npy1r^{tm1.1(cre/GFP)Rpa}
Name: targeted mutation 1.1, Richard D Palmiter
MGI accession ID: MGI:5804208
Generation method: Targeted
Attributes: Recombinase-expressing; Reporter
Synonyms: Npy1r^cre:GFP
Marker symbol: Npy1r
Marker name: neuropeptide Y receptor Y1
Marker synonyms: NPY-1; NPY1-R; Npyr; Y1-R
Chromosome: 8
Strain of origin: (129S6/SvEvTac x C57BL/6NCrl)F1
Expressed genes: cre,cre recombinase,bacteriophage P1
Site of expression: When crossed with mice expressing a floxed stop reporter cre expression is detected in the anterior-dorsal, anterior ventral, posterior dorsal and posterior ventral medial amygdala. Although GFP fluorescence is incorporated in the targeting construct, it is too low to be visualized directly or through immunohistochemistry.
Molecular note: A cre/GFP fusion gene with a neo cassette was inserted just 5' fo the normal initiation codon for Npy1r gene. The neo cassette was then removed by action of FLP recombinase.