B6;129S1-Dmrtb1^tm1Zark/J

Stock number: 035792
Product name: Dmrt6^flox
Research areas: Developmental Biology Research, Neurobiology Research, Reproductive Biology Research, Research Tools

Description

Dmrt6^flox mutant mice possess loxP sites flanking exon 1 of the Dmrtb1 (DMRT-like family B with proline-rich C-terminal, 1 or Dmrt6) gene and may be useful in generating conditional mutations to study spermatogenesis.

Detailed description

Dmrtb1 (DMRT-like family B with proline-rich C-terminal, 1 or Dmrt6) encodes a DNA-binding transcription factor involved in transitioning spermatogonial differentiation and mitotic proliferation to spermatocyte differentiation and meiosis. Dmrt6 is expressed in late mitotic spermatogonia as well as in the fetal brain and at low levels in the ovary and pancreas. These conditional Dmrt6^fl mice possess loxP sites flanking exon 1 of the Dmrtb1 gene. Exon 1 includes the DM domain, a zinc finger-like DNA-binding motif. Mice homozygous for the mutation are viable and fertile. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have the exon 1 deleted in cre-expressing tissues.

For example, when bred to mice with widespread Cre recombinase expression (such as Tg(ACTB-cre)2Mrt, Stock No. 033984), resulting knockout male offspring exhibit small testes and lack mature spermatozoa in the seminiferous tubules and epididymis. Female knockout mice are normal and fertile with no apparent ovarian defects.

Development

The targeting construct was designed to insert a loxP site upstream of exon 1 and the proximal promoter, followed by an FRT-flanked neomycin cassette and a second loxP site in the Dmrtb1 gene. Exon 1 includes the DM domain, a zinc finger-like DNA-binding motif. The construct was electroporated into 129S1/Sv-derived CJ7 embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts. Chimeric males were crossed to C57BL/6J females. The colony was crossed to C57BL/6J for approximately 7 generations by the donating laboratory (see SNP note below). Upon arrival, mice were bred to C57BL/6J (000664) for at least one generation to establish the colony.

In 2021, 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. Many of the 43 markers throughout the genome were segregating with 129, suggesting an incomplete backcross. Also, two of the 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating on Chromosomes 15 and 19. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed genetic background.

Allele

Symbol: Dmrtb1^tm1Zark
Name: targeted mutation 1, David Zarkower
MGI accession ID: MGI:5705336
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed)
Synonyms: Dmrt6^flox; Dmrt6^neo
Marker symbol: Dmrtb1
Marker name: DMRT-like family B with proline-rich C-terminal, 1
Marker synonyms: Dmrt6; Prp13; RGD1560921
Chromosome: 4
Strain of origin: 129S1/Sv-Oca2⁺ Tyr⁺ Kitl⁺
Molecular note: A loxP site was inserted upstream of exon 1 and an FRT flanked pgk-neo cassette and loxP site were inserted downstream of exon 1 via homologous recombination.