C57BL/6-Del(7Saa3-Saa2)738Lvh/J

Stock number: 034856
Product name: Saa^-
Research areas: Immunology, Inflammation and Autoimmunity Research

Description

Saa^- mice carry a CRISPR/Cas9-generated deletion of the Saa3, Saa4, Saa1, and Saa2 serum amyloid A genes, clustered on mouse Chromosome 7. This strain is useful in studies of infection processes.

Detailed description

Serum amyloid A (SAA) proteins, which can bind vitamin A (retinol), are strongly induced in the liver by systemic infection and in the intestine by bacterial colonization.

These Saa^- mice carry a CRISPR/Cas9-generated deletion of the Saa3, Saa4, Saa1, and Saa2 serum amyloid A genes, clustered on mouse Chromosome 7. SAA transcript and protein expression are lost in this deletion allele. No SAAs are detected in the sera of homozygotes infected intraperitoneally (i.p.) with Salmonella typhimurium. Serum retinol concentrations in the infected homozygous knock-out mice are much lower than those found in infected wildtype mice.

Development

The Saa3, Saa4, Saa1, and Saa2 genes, clustered on mouse Chromosome 7 were deleted using CRISPR/Cas9 methodologies. Guide RNAs and Cas9 mRNA were injected into C57BL/6J embryos. Resultant mice were crossed with C57BL/6J inbred mice for 1 generation. This strain was maintained on a C57BL/6J genetic background by the donating laboratory (see SNP note below). This is founder line 738.

In 2020, a 48 SNP (single nucleotide polymorphism) panel analysis, with 43 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 males sent to The Jackson Laboratory Repository. Also, 4 of the 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating, including the rd8 recessive mutation associated with retinal degeneration on Chromosome 1 within the Crb1 locus. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6N;C57BL/6J genetic background.

Allele

Symbol: Del(7Saa3-Saa2)738Lvh
Name: deletion, Chr 7, Lora Hooper 738
MGI accession ID: MGI:6393613
Generation method: Endonuclease-mediated
Attributes: Null/Knockout
Synonyms: Saa^-
Marker symbol: Del(7Saa3-Saa2)738Lvh
Marker name: deletion, Chr 7, Lora Hooper 738
Chromosome: 7
Strain of origin: C57BL/6J
Molecular note: CRISPR/Cas9 genome editing is used to generate guide RNAs that target regions upstream and downstream of the Saa locus and delete Saa3, Saa4, Saa1, and Saa2, respectively, clustered on mouse Chromosome 7.