STOCK Gprc6a^tm1.1Kry/J

Stock number: 034071
Product name: Gprc6a floxed
Research areas: Internal/Organ Research, Metabolism Research, Reproductive Biology Research

Description

Gprc6a floxed mice possess loxP sites flanking exon 2 of the G protein-coupled receptor, family C, group 6, member A (Gprc6a) gene. These floxed mice are useful when studying the role of osteocalcin in bone remodeling and energy metabolism.

Detailed description

Gprc6a floxed mice possess loxP sites flanking exon 2 of the G protein-coupled receptor, family C, group 6, member A (Gprc6a) gene. This gene is expressed in Leydig cells in testes, but not in follicular cells of the ovary. Gprc6a expression peaks within the first week of life, when circulating testosterone levels are elevated. Expression then decreases before increasing again at 6 weeks of age, when circulating levels of testosterone also rebound. Gprc6a is a receptor for osteocalcin, bone protein secreted by osteoblasts that regulates bone remodeling and energy metabolism. Mice that are homozygous for this floxed allele are viable and fertile. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have exon 2 deleted in the Cre-expressing tissues.

When bred to Cyp17iCre mice (Stock No. 028547), expressing iCre in ovarian and testicular cells, male mice exhibit reduction in testes size and weight, epididymis and seminal vesicle weights, sperm counts and circulating testosterone levels, and Leydig cell area. The expression of gonadotropin regulated testicular helicase (Grth), a regulator of spermatogenesis, and the three genes controlling testosterone biosynthesis that are regulated by osteocalcin were also reduced.

Development

The Gprc6a floxed targeting vector was designed to insert a loxP site upstream of exon 2, and a frt-flanked neomycin selection cassette followed by a second loxP site downstream of exon 2 of the G protein-coupled receptor, family C, group 6, member A (Gprc6a) gene. The construct was electroporated into C57BL/6J embryonic stem (ES) cells and correctly targeted ES cells were injected into recipient blastocysts. Chimeras were bred with ACTB:FLPe mice (Stock No. 005703) to remove the neo cassette, and the progeny were then crossed to remove the FLPe-expressing transgene. Mice were then bred to 129SvE/Tac mice for at least 8 generations by the donating lab (see SNP results below). Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize 129S1/SvImJ oocytes (Stock No. 002448).



In 2019 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. Three of the 43 markers on Chromosomes 1, 6 and 15 were segregating with B6 suggesting an incomplete backcross.

Allele

Symbol: Gprc6a^tm1.1Kry
Name: targeted mutation 1.1, Gerard Karsenty
MGI accession ID: MGI:4949090
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Synonyms: Gprc6a^f
Marker symbol: Gprc6a
Marker name: G protein-coupled receptor, family C, group 6, member A
Marker synonyms: bA86F4.3; GPCR
Chromosome: 10
Strain of origin: C57BL/6J
Molecular note: A loxP site was inserted upstream of exon 2. An FRT-flanked neo cassette with a 3' loxP site was inserted downstream of exon 2. Flp-mediated recombination removed the neo cassette, leaving exon 2 floxed.