These mice carry a spontaneous mutation at the Npr3 locus characterized by arachnodactyly, thoracic kyphosis, a lack of normal body fat deposits, and delayed endochondrial ossification.Read More +
Homozygous mutants are identifiable as young as six days of age by their elongated bodies and digits and a conical extension of the body at the base of the tail. Older mice are extremely thin and exhibit arachnodactyly, thoracic kyphosis and, often, kinks in the tail and/or sacrum. Upon necropsy, mice are found to lack normal body fat deposits. No significant craniofacial defects have been observed. Skeletal analysis demonstrated delayed endochondrial ossification, most obvious in the hind- and forepaws but affecting the entire skeleton. Retarded ossification was apparent in neonates and presumably occurs in utero.Both male and female Npr3lgj-2J/Npr3lgj-2Jmice are fertile and can breed.
An earlier mutation at this locus, Npr3lgj, in the BALB/cJ inbred strain (stock number 003206) produces a similar phenotype. However, homozygous males of this stock number 003206 cannot reproduce because their more extreme spinal defect prevents them from mounting.
The Npr3lgj-2J mutation occurred spontaneously in 1996 in the DBA/2J inbred strain at The Jackson Laboratory. It was initially outcrossed once to a B6D2F1 female via ovarian transplant and subsequently has been maintained through backcross-intercross breeding. Thus, this strain does have a small amount of C57BL/6J in its genetic background but the mutant allele arose on a DBA/2J chromosomal segment. This mutation was originally named lgj2J, longjohn-2J. When it was identified as a mutation of the Npr3 gene, it was renamed Npr3lgj-2J.
|Allele Name||longjohn 2 Jackson|
|Gene Symbol and Name||Npr3, natriuretic peptide receptor 3|
|Strain of Origin||DBA/2J|
|General Note||Genbank: AF131863|
|Molecular Note||A C-to-T transition mutation at coding nucleotide 283 (c.283C>T) introduces a premature stop codon at glutamine codon 95 (p.Q95*).|
When using the longjohn 2 Jackson mouse strain in a publication, please cite the originating article(s) and include JAX stock #003507 in your Materials and Methods section.