C57BL/6N-Sox6^tm1(cre)Awar/J

Stock number: 040635
Product name: Sox6-FSF-Cre
Research areas: Cell Biology Research, Neurobiology Research, Research Tools

Description

Sox6-FSF-Cre knock-in/knock-out mice express a FLP-inducible cre under the control of the endogenous Sox6 promoter. The insertion of the FSF-Cre sequence abolishes Sox6 expression. FLP-mediated recombination results in the excision of an frt-flanked STOP/neo sequence, enabling the tissue and time-dependent expression of Cre. These mice may be useful when studying the role of SOX6 in embryonic development and determination of the cell fate.

Detailed description

Sox6-FSF-Cre knock-in/knock-out mice have an FRT-STOP-Puro-FRT cassette and a cre gene inserted in the intronic region between exons 2 and 3 of the endogenous SRY (sex determining region Y)-box 6 (Sox6) gene. The insertion of the FSF-Cre sequence abolishes Sox6 expression. Sox6 encodes a transcription factor involved in the lineage determination and differentiation of discrete cell types from embryonic development onto adulthood. These cell types include chondrocytes, interneurons, and skeletal and cardiac muscle cells. In the absence of FLP, Cre expression is prevented by the STOP cassette. After removal of the STOP cassette, Cre is expressed. When mice are further bred with mice containing loxP-flanked sequences, Cre-mediated recombination will result in deletion of floxed sequences in Cre-expressing cells of the offspring. Mice that are homozygous for this knock-in/knock-out allele are embryonic lethal.

The donating investigator bred these Sox6-FSF-Cre mice to the dual-recombinase responsive fluorescent reporter line, RC::FrePe (Stock No. 029486), which is a conditional allele designed with both an frt-flanked STOP cassette and a loxP-flanked mCherry::STOP cassette preventing transcription of the EGFP green fluorescent protein gene. Further breeding to Th-2A-Flpo mice results in the removal of the flanked STOP cassettes by FLP- and Cre-recombination. In these mice, the intersectional reporter RC::Frepe labels only postmitotic cells expressing Sox6. EGFP fluorescence is expected in only cells/tissues expressing both FLP recombinase and Cre recombinase. Specifically, 97.7% of EGFP⁺ neurons of the substantia nigra pars compacta (SNc) were SOX6⁺ and 82.7% of SOX6⁺TH⁺ of the SNc were EGFP⁺. Some fluorescence is also seen in cell populations outside the midbrain.

Of note, the donating investigator made a panel of mice useful for studying the role of SOX6 in embryonic development and determination of the cell fate:
Sox6-FSF-Cre mice are flp-inducible and are available as Stock No. 040635
Sox6-Cre mice are available as Stock No. 040636
Sox6-CreER^T2 are available as Stock No. 040638

Development

The Sox6-FSF-Cre targeting vector has an FRT-STOP-Puro-FRT cassette inserted in the intronic region between exons 2 and 3 of the endogenous SRY (sex determining region Y)-box 6 (Sox6) gene. A NLS-Cre-polyA cassette was also inserted into the Sox6 gene downstream of the FRT-STOP-Puro-FRT cassette, in-frame with the endogenous ATG codon. The construct was electroporated into C57BL/6NTac-derived PRX-B6N embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts. The chimeric animals were crossed with C57BL/6NCrl females for germline transmission. The donating investigator reports the resulting Sox6-FSF-Cre mice were backcrossed to C57BL/6NCrl for an unknown number of generations. Cryopreserved sperm was sent to The Jackson Laboratory. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6NJ oocytes (Stock No. 005304).

Allele

Symbol: Sox6^tm1(cre)Awar
Name: targeted mutation 1, Rajeshwar Awatramani
MGI accession ID: MGI:6726338
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Recombinase-expressing
Synonyms: Sox6-FSF-Cre
Marker symbol: Sox6
Marker name: SRY (sex determining region Y)-box 6
Marker synonyms: HSSOX6; SOXD; TOLCAS
Chromosome: 7
Strain of origin: C57BL/6NTac
Molecular note: By homologous recombination in ES cells, FRT-STOP-Puro-FRT cassette was inserted into the intronic region between exons 2 and 3 and a NLS-Cre-polyA was inserted into the Sox6 gene in-frame to the endogenous ATG.