STOCK Dnaja3^tm1.1Xww/J

Stock number: 041715
Product name: Dnaja3^flx
Strain synonyms: Dnaja3 CKO
Research areas: Cancer Research, Cell Biology Research, Metabolism Research, Research Tools

Description

Dnaja3^flx floxed mice have loxP sites flanking exons 1-2, including the promoter, of the Dnaja3 gene. This strain may be useful for studying the role of DNAJA3 in immunology and cancers, including hepatocellular carcinoma (HCC).

Detailed description

Dnaja3^flx floxed mice have loxP sites flanking exons 1-2, including the promoter, of the DnaJ heat shock protein family (Hsp40) member A3 (Dnaja3) gene. Dnaja3 encodes a mitochondrial protein that mediates several cellular processes including proliferation, survival, and apoptotic signal transduction. DNAJA3 also plays a critical role in tumor suppression and, as a mitochondrial co-chaperone, DNAJA3 has been identified as a genetic determinant of human nonalcoholic steatohepatitis (NASH) which is often associated with obesity, diabetes, and metabolic syndrome and can progress to cirrhosis, hepatocellular carcinoma (HCC), or liver failure.

Mice that are homozygous for the Dnaja3^flx allele are viable and fertile. When these mice are bred to mice that express Cre recombinase, resulting offspring will have the promoter and exons 1-2 deleted in Cre expressing tissues.

These mice were crossed to Albumin-Cre mice (Stock No. 003574), with liver-specific Cre expression, hepatocyte-specific Dnaja3 knock-out mice recapitulate key features of human nonalcoholic steatohepatitis (NASH)-dependent hepatocellular carcinoma (HCC) characterized by significant mitochondrial dysfunction, which was accompanied by excessive lipid accumulation, inflammatory responses, and male-predominant tumor incidence. When also bred to p53^LoxP mice (Stock No. 008462). Trp53 ablation accelerates HCC and diminishes sex differences in tumor development.

Development

A targeting vector was designed to insert a single loxP site upstream of exon 1 of the DnaJ heat shock protein family (Hsp40) member A3 (Dnaja3) gene and a second loxP site was inserted downstream of exon 2. An FRT-flanked neomycin resistance (neo) cassette was inserted between exon 2 and the 3' loxP site, within the floxed region, in opposite orientation to the Dnaja3 gene. The construct was electroporated into 129S6/SvEvTac-derived TC-1 embryonic stem (ES) cells and correctly targeted ES cells were injected into C57BL/6 blastocysts. Dnaja3^Tg mice were subsequently bred to CAG-Flp mice on a C57BL/6 genetic background to remove the neo cassette. Resulting Dnaja3^flx floxed offspring, lacking the neo cassette, were bred to Albumin-Cre mice (Stock No. 003574) before being backcrossed to C57BL/6J mice for at least 5 generations by the donating laboratory (see SNP note below). The Albumin-Cre allele was bred out of the mice that were sent to The Jackson Laboratory. Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).



In 2026, 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. One of the 43 markers throughout the genome were segregating with an unknown source, and 3 markers were segregating with 129. Also, 3 of the 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed genetic background.

Allele

Symbol: Dnaja3^tm1.1Xww
Name: targeted mutation 1.1, Xin Wei Wang
MGI accession ID: MGI:8347731
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed)
Synonyms: Dnaja3^flx
Marker symbol: Dnaja3
Marker name: DnaJ heat shock protein family (Hsp40) member A3
Marker synonyms: 1200003J13Rik; 1810053A11Rik; HCA57; hTID-1; TID1; Tid-1; Tid1-L; Tid1-S
Chromosome: 16
Strain of origin: 129S6/SvEvTac
Molecular note: A targeting vector was designed to insert a single loxP site upstream of exon 1 of the DnaJ heat shock protein family (Hsp40) member A3 (Dnaja3) gene and a second loxP site was inserted downstream of exon 2. An FRT-flanked neomycin resistance (neo) cassette was inserted between exon 2 and the 3' loxP site, within the floxed region, in opposite orientation to the Dnaja3 gene. Flp recombinase removed the neo cassette.