Mrap2 KO mice have a frt-flanked β-gal gene and neo cassette preventing widespread expression of the melanocortin 2 receptor accessory protein 2 (Mrap2) gene. Exon 4 is flanked by loxP sites making this strain useful for conditional deletion as well. These mice may be suitable for applications related to energy homeostasis and food intake.
Julien A Sebag, University of Iowa
Mrap2 KO mice have a β-galactosidase gene and a neo cassette preventing expression of the melanocortin 2 receptor accessory protein 2 (Mrap2) gene. Also, loxP sites flank exon 4. MRAP2 is a G-Protein Coupled Receptor accessory protein that regulates energy homeostasis and food intake through receptors such as melanocortin-4 receptor (MC4R) and prokineticin receptor 1 (PKR1). Homozygous Mrap2 KO mice are viable, fertile, and severely obese.
A conditional ready floxed allele can be created by flp recombinase expression in mice carrying this allele. Subsequent cre expression results in the deletion of exon 4. If cre expression occurs without flp expression, a β-galactosidase reporter knockout mouse will be created.
C57BL/6N-Atm1Brd-derived JM8A3.N1 embryonic stem (ES) cells containing a targeted mutation of the melanocortin 2 receptor accessory protein 2 (Mrap2) gene were obtained from The European Conditional Mouse Mutagenesis Program (EUCOMM). The mutant allele has, from 5’ to 3’, a FRT site, a β-galactosidase and polyA sequence, a loxP site, a neomycin resistance (neo) cassette, a second FRT site, and loxP sites flanking exon 4. Targeted ES cells were injected into blastocysts. The resulting chimeric animals were tested for germline transmission. Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6NJ oocytes (Stock No. 005304).
A 32 SNP (single nucleotide polymorphism) panel analysis, with 27 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 27 markers throughout the genome suggested a C57BL/6 genetic background, all 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/6J ; C57BL/6N genetic background.
|Allele Name||targeted mutation 1a, Wellcome Trust Sanger Institute|
|Allele Type||Targeted (Conditional ready (e.g. floxed), Reporter, Null/Knockout)|
|Gene Symbol and Name||Mrap2, melanocortin 2 receptor accessory protein 2|
|Strain of Origin||C57BL/6N-Atm1Brd|
|Molecular Note||The L1L2_Bact_P cassette was inserted at position 87057386 of Chromosome 9 upstream of the critical exon(s) (Build GRCm39). The cassette is composed of an FRT site followed by lacZ sequence and a loxP site. This first loxP site is followed by a neomycin resistance gene under the control of the human beta-actin promoter, SV40 polyA, a second FRT site and a second loxP site. A third loxP site is inserted downstream of the targeted exon(s) at position 87058188. The critical exon(s) is/are thus flanked by loxP sites. A "conditional ready" (floxed) allele can be created by flp recombinase expression in mice carrying this allele. Subsequent cre expression results in a knockout mouse. If cre expression occurs without flp expression, a reporter knockout mouse will be created. Further information on targeting strategies used for this and other IKMC alleles can be found at http://www.informatics.jax.org/mgihome/nomen/IKMC_schematics.shtml|
When maintaining a live colony, homozygous mice may be bred together.
When using the MRAP2 KO mouse strain in a publication, please cite the originating article(s) and include JAX stock #029050 in your Materials and Methods section.