B6.Cg-Gt(ROSA)26Sor^{tm2(CAG-SOX8)Vlf}/J

Stock number: 039626
Product name: R26^SOX8
Research areas: Developmental Biology Research, Internal/Organ Research, Research Tools

Description

R26^SOX8 contain a Cre-inducible human SOX8 cDNA, with an N-terminal 3xFLAG tag, inserted into the Gt(ROSA)26Sor locus. These mice may be useful when studying the role of SOX8 in embryonic development and determination of the cell fate.

Detailed description

R26^SOX8/SOX8 mice contain a Cre-inducible knock-in of the human SRY (sex-determining region Y)-box 8 (SOX8) cDNA, with an N-terminal 3xFLAG tag, inserted into the Gt(ROSA)26Sor locus. A floxed Neo/STOP cassette prevents 3xFLAG-SOX8 expression in the absence of Cre recombinase. After removal of the loxP-flanked cassette, 3xFLAG-SOX8 is produced in Cre-expressing cells and daughter cells.

Sox8 encodes a transcription factor involved in the regulation of lineage fate determination and differentiation of discrete cell types from embryonic development onto adulthood. These cell types include neural crest, glial, neuronal, skeletal, and Sertoli cells.

R26^SOX8/SOX8 mice are viable, look normal throughout life, and are fertile.

R26^SOX8/+ mice carrying a Prx1Cre transgene (Stock No. 005584), which is active in early limb bud mesenchymal cells and some sternum progenitor cells, are viable, fertile and behave normally, but show a mild delay in endochondral ossification. R26^SOX8/SOX8Prx1Cre mice exhibit very short limbs with midshaft bone fractures due to cartilage growth plate defects and severely impaired bone formation. They show a drastic health decline in the second week postnatally, likely as a consequence of their multiple limb bone fractures.

Development

The R26^SOX8 targeting vector was designed with (from 5' to 3') a ubiquitously expressed CAG promoter, a loxP-flanked stop cassette containing a neomycin resistance (neo) cassette and three polyadenylation signals, and 3xFLAG tagged human SRY (sex determining region Y)-box 8 (SOX8) cDNA sequence followed by a polyadenylation signal. This targeting vector also included 5' and 3' arms of homology for site-directed recombination into the Gt(ROSA)26Sor locus. The construct was electroporated into (C57BL/6 x 129S4/SvJae)F1-derived C2 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts and the chimeric mice were bred to C57BL/6J mice (Stock No. 000664) for at least 5 generations by the donating laboratory (see SNP note below). Cryopreserved sperm was sent to The Jackson Laboratory. Upon arrival, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes to establish our live colony.

In 2025, 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 rederived living colony at The Jackson Laboratory Repository. One of the 43 markers throughout the genome was segregating with 129, on Chromosome 10. Also, 3 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: Gt(ROSA)26Sor^{tm2(CAG-SOX8)Vlf}
Name: targeted mutation 2, Veronique Lefevbre
MGI accession ID: MGI:7665208
Generation method: Targeted
Attributes: Inserted expressed sequence; Epitope tag
Synonyms: R26^SOX8
Marker symbol: Gt(ROSA)26Sor
Marker name: gene trap ROSA 26, Philippe Soriano
Marker synonyms: beta geo; Gtrgeo26; Gtrosa26; R26; ROSA26; SETD5-AS1; Thumpd3as1
Chromosome: 6
Strain of origin: (C57BL/6 x 129S4/SvJae)F1
Molecular note: The targeting vector was designed to insert (from 5' to 3') a ubiquitously expressed CAG promoter, a loxP site flanked stop cassette containing a neomycin resistance (neo) cassette and three polyadenylation signals, and 3xFLAG tagged human SRY (sex determining region Y)-box 8 (SOX8) cDNA sequence followed by a polyadenylation signal into the Gt(ROSA)26Sor locus.