B6.Cg-Yars1^tm1.1Xly/J

Stock number: 039925
Product name: Yars^ΔNLS
Research areas: Cell Biology Research, Metabolism Research, Mouse/Human Gene Homologs, Neurobiology Research, Research Tools, Sensorineural Research

Description

The Yars^ΔNLS mice have a disrupted nuclear localization signal (NSL) in the tyrosyl-tRNA synthetase 1 (Yars1) gene, also known as TyrRS, preventing the nuclear translocation. TyrRS functions as a stress response protein through its cytosol-nucleus translocation to maintain cellular homeostasis. The homozygous Yars^ΔNLS mice are viable and fertile but show reduced lean mass and reduced fat mass. The Yars^ΔNLS mice exhibit improved insulin sensitivity and reduced insulin levels, yet maintain normoglycemia, indicative of enhanced insulin action. They also develop progressive hearing loss. They may be useful in studies of the function of nuclear TyrRS.

Detailed description

The Yars^ΔNLS mice have a targeted mutation in the nuclear localization signal (NSL) sequence of the tyrosyl-tRNA synthetase 1 (Yars1) gene, also known as TyrRS. The disruption of the NSL regulatory sequence from KKKLKK to NNKLNK resulted in TyrRS being predominantly excluded from the nucleus while allowing enzymatic activity in vitro. The homozygous Yars^ΔNLS mice have a smaller body weight in both sexes attributed to consistently smaller lean mass and decrease in fat accumulation throughout the life span but are otherwise viable and fertile; no gross lesions were found at 2 months. The heterozygous Yars^ΔNLS mice also exhibit a smaller body weight to a lesser degree. During adulthood, Yars^ΔNLS mice show TyrRS functional changes across different tissues resulting in abnormal phonotypes including hearing loss, enhanced energy expenditure, and reduced adiposity, impacting insulin signaling. The model may be useful to elucidate the nuclear functions of TyrRS in the maintenance of fat storage and hearing relating to how protein synthesis relates to metabolic regulation.

Development

A targeting vector containing exon 7 of the Yars1 gene with the NLS sequence mutated from ₂₄₂KKKLKK₂₄₇ to ₂₄₂NNKLNK₂₄₇ corresponding to 945-962 aa in mRNA and 19897-20032 nt in the DNA sequence with 3' and 5' homology arms, was electroporated into mouse embryonic stem (ES) cells of unknown origin. Correctly targeted clones were screened by PCR and used for blastocyst injection. After screening and confirmation of germline transmission, founder mice were bred with FLP transgenic mice of unknown genetic background to delete FRT flanked Neomycin, thereby generating Yars^ΔNLS (Neo-Out) strain. mRNA expression of the mutant allele was confirmed through RT-PCR, and functional disruption of nuclear import was confirmed by Western blot. These mice were crossed with C57BL/6J mice from the Scripps Rodent Breeding Colony at least 7 generations, and the heterozygous colony is maintained in the C57BL/6J genetic background by the donating laboratory. Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

Allele

Symbol: Yars1^tm1.1Xly
Name: targeted mutation 1.1, Xiang-Lei Yang
MGI accession ID: MGI:7764500
Generation method: Targeted
Attributes: Altered localization
Synonyms: Yars^deltaNLS
Marker symbol: Yars1
Marker name: tyrosyl-tRNA synthetase 1
Marker synonyms: CMTDIC; IMNEPD2; TYRRS; YARS; YRS; YTS
Chromosome: 4
Strain of origin: Not Specified
Molecular note: The nuclear localization signal in exon 7 was modified from KKKLKK to NNKLNK and an FRT-flanked neo cassette was inserted downstream of exon 7 via homologous recombination. Flp-mediated recombination removed the neo cassette.