B6.Cg-chtl Nos2^tm1Lau/GrsrJ

Stock number: 004684
Product name: Chocolate-like
Research areas: Dermatology Research, Immunology, Inflammation and Autoimmunity Research, Neurobiology Research

Description

The chtl, chocolate-like, spontaneous mutation was discovered at The Jackson Laboratory in 1998 in the B6.129P2-Nos2^tm1Lau/J (Stock # 002609) strain at generation N7F4+F16. These mice also carry the Nos2^tm1Lau targeted mutation.

Detailed description

This mutant has an overall lighter coat, tail and ears than a black +/+ control. Both males and females breed and it is maintained as a homozygous stock.

Development

This chtl spontaneous mutation was discovered at The Jackson Laboratory in 1998 in the B6.129P2-Nos2^tm1Lau/J (Stock # 002609) strain at generation N7F4+F16.

Allele

Symbol: Nos2^tm1Lau
Name: targeted mutation 1, Victor E Laubach
MGI accession ID: MGI:1857228
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Nos2
Marker name: nitric oxide synthase 2, inducible
Chromosome: 11
Strain of origin: 129P2/OlaHsd
Molecular note: A neomycin cassette replaced exons 12 and 13 of the gene, which encode the calmodulin-binding domain. Northern and Western blots of IFNg/LPS-stimulated peritoneal macrophages showed no detectable Nos2 mRNA or protein, respectively.

Allele

Symbol: chtl
Name: chocolate-like
MGI accession ID: MGI:2675597
Generation method: Spontaneous
Marker symbol: chtl
Marker name: chocolate-like
Chromosome: 7
Strain of origin: B6.129P2-Nos2^tm1Lau/J
Molecular note: The chocolate-like spontaneous mutation was found at The Jackson Laboratory in 1998. A test for allelism to the cht locus demonstrated that the two mutations are in pseudoalleles or that modifier genes in the two background strains can affect the phenotype expression.
General note: A test for allelism with homozygous cht mouse mated to a homozygous mutant mouse produced 32/32 progeny with a dull grey phenotype, unlike cht or a/a . These results suggested chtl is a new allele of the cht gene that produces a different phenotype from the original cht allele. When two matings of the grey color F1s from the allele test progeny were mated together, however, they produced segregating litters for a total of 10 cht looking mice and 3 normal black a/a mice. The appearance of the black mice means either the two mutations are pseudoalleles or modiefier genes can affect the phenotype expresssion.