B6.FVB-Tg(Ada*-cre)5Xiay/J

Stock number: 036543
Product name: ADA-Cre, Tpbpar/Adaf-AdaP-Cre

Research areas: Research Tools

Description

Tpbpar/Adaf-AdaP-Cre transgenic mice express a cre recombinase directed by a mouse basal Ada (adenosine deaminase) promoter and a chimeric Tpbpar/Ada placental enhancer. Nuclear localized cre recombinase activity is observed in the placenta.

Detailed description

Tpbpar/Adaf-AdaP-Cre transgenic mice express cre recombinase under the direction of the mouse Ada (adenosine deaminase) promoter and a chimeric Tpbpa/Ada placental enhancer. Ada and Tpbpa (trophoblast specific protein alpha) contain regulatory fragments that allow specific expression in the trophoblast cell lineage throughout placental development. Using the chimeric  Tpbpa/Ada enhancer, a basal Ada promoter and a nuclear localization signal, cre recombinase expression is directed to the placenta but not in the maternal organs examined or in the fetus.

When crossed with a strain containing loxP sites flanking the sequence of interest, the offspring are useful for generating cre-mediated targeted gene deletions in the placenta. Hemizygous mice are viable and fertile. The donating investigator has not attempted to generate homozygotes.

Development

The Tpbpar/Adaf-AdaP-Cre transgenic construct contains a Tpbpar (trophoblast specific protein alpha) enhancer in reverse orientation, a 1.8 kb adenosine deaminase enhancer in forward orientation (Adaf), and a 0.8 kb basal Ada promoter directing expression of cre recombinase with a nuclear localization signal (NLS). The linearized construct was microinjected into the pronuclei of FVB/N zygotes. Founder line 5 contains 8 copies of the transgene and was bred to FVB/N male mice. Mice were backcrossed to C57BL/6J for over 10 generations by the donating laboratory (see SNP note below). 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 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. One of the 5 markers that determine C57BL/6J from C57BL/6N was found to be segregating on Chromosome 8. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6N;C57BL/6J genetic background.

Allele

Symbol: Tg(Ada*-cre)5Xiay
Name: transgene insertion 5, Yang Xia
MGI accession ID: MGI:5444884
Generation method: Transgenic
Attributes: Recombinase-expressing
Synonyms: Tpbpar/Adaf-AdaP-Cre
Marker symbol: Tg(Ada*-cre)5Xiay
Marker name: transgene insertion 5, Yang Xia
Chromosome: UN
Strain of origin: FVB
Molecular note: A construct was generated with a Tpbpa/Ada chimeric enhancer and Ada gene basal promoter ligated to the cre cDNA containing a nuclear localization signal (NLS). The 0.4 kb trophoblast specific protein alpha enhancer was cloned in reverse orientation (Tpbpar) with the 1.8 kb adenosine deaminase enhancer in forward orientation (Adaf); this chimeric enhancer was combined with the 0.8 kb basal Ada promoter (AdaP) in the transgenic vector . The linearized construct was injected into pronuclei of FVB zygotes. Six founders were obtained and all showed similar transgene expression patterns. Data from the mouse with the highest transgene copy number (line 5) is presented in the original reference.