SH1/LeJ

Stock number: 000271
Product name: chinchilla shaker1
Research areas: Dermatology Research, Developmental Biology Research, Mouse/Human Gene Homologs, Neurobiology Research, Sensorineural Research

Description

This inbred mutant strain carries the shaker 1 (Myo7a^sh1) mutation and exhibits circling, head-tossing, deafness, and hyperactivity.

Detailed description

Mice homozygous for the shaker 1 spontaneous mutation (Myo7a^sh1) show circling, head-tossing, deafness, and hyperactivity characteristic of this type of mutant mice. Viability is normal, and breeding ability is high for a circling mutant. Homozygous mutant mice are most often deaf and swim well on the surface of water up to 4 weeks of age and more but lose the ability later. The degenerative changes of the labyrinth may occur a little later than in some of the other waltzing mutants. By light microscopy, the changes are seen to consist of degeneration of the organ of Corti, the spiral ganglion, and the stria vascularis in the cochlea, and of the saccular macula and the vestibular ganglion in the vestibular labyrinth.

Development

The shaker 1 (Myo7a^sh1) strain originated in 1957 with two FS/Ei siblings at F5 mated. One sibling was also mated to a C57BL/6J and the offspring of the two FS/Ei mice were mated to a C3HeB/FeJ. Several within stock matings were made from both crosses and 2 siblings were each mated to a C3HeB/FeJ. Two generations were stock bred and the chinchilla shaker1 genotype was selected for inbreeding with the Myo7a^sh1 locus segregating. It was cryopreserved in 1989 by mating chinchilla shaker1 (Tyr^c-ch Myo7a^sh1/Tyr^c-ch Myo7a^sh1) males to chinchilla but shaker1 heterozygous (Tyr^c-ch Myo7a^sh1/Tyr^c-ch +) females at F96.

Allele

Symbol: Myo7a^sh1
Name: shaker 1
MGI accession ID: MGI:1856716
Generation method: Spontaneous
Marker symbol: Myo7a
Marker name: myosin VIIA
Chromosome: 7
Strain of origin: BALB at F12
Molecular note: A G-to-C transversion mutation results in an arginine to proline change at position 502 in the encoded protein (p.R502P). This mutation lies within the head domain of the protein. Northern blot analysis indicated that mRNA expression, size, and stability were unaffected. Immunoblot analysis showed that normal levels of the protein was expressed.

Allele

Symbol: Tyr^c-ch
Name: chinchilla
MGI accession ID: MGI:1855977
Generation method: Spontaneous
Marker symbol: Tyr
Marker name: tyrosinase
Chromosome: 7
Strain of origin: fancier's stock
Molecular note: The mutation in the chinchilla allele was found to be a G-to-A point mutation that results in an amino acid change at position 482 or 464 from alanine to threonine (p.A482T for pre-protein, p.A464T for mature protein).