B6.FVB-Tg(CD34-tTA,-CD34)1Dgt/KatmJ

Stock number: 034038
Product name: human CD34-tTA , hCD34-tTA
Research areas: Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

hCD34-tTA transgenic mice function as a Tet-Off tool that allows doxycycline controlled expression of the human CD34 gene on multiple cell types including vascular endothelial cells and hematopietic stem cells.

Detailed description

hCD34-tTA transgenic mice express the human CD34 gene under the direction of the human promoter. CD34 is a type I transmembrane phosphoglycoprotein expressed on early hematopoietic stem cells, progenitor cells and endothelial cells and is associated with cell adhesion and migration.  CD34+ cells have been identified in multiple types of tumors including preB-ALL, AML, GI stromal tumors and Karposi's sarcoma. Mice homozygous for the transgene are viable and fertile and exhibit no obvious phenotype.  When mated to a second transgenic strain carrying a gene of interest under the regulatory control of a tetracycline-responsive promoter element (TRE or tetO), expression of the target gene in endothelial and hematopoietic stem/progenitors cells is turned off with administration of the tetracycline analog, doxycycline (dox). These hCD34-tTA transgenic mice may be useful for research in multipotent hematopoietic stem cells, bone marrow transplantation, and cancer.
For example, when combined with mice carrying Tg(tetO-HIST1H2BJ/GFP)47Efu on the matching C57BL/6 background (Stock No. 034039), administration of doxycycline to bitransgenic animals can be used to identify and monitor hematopoietic stem cell division.

Development

The HCD34-tTA transgene was designed with a tetracycline transactivator (tTA) gene inserted into the promoter of the human CD34 gene, an IRES (internal ribosome entry site), followed by human CD34 exon 1 and 2.3 kb of intron 1. A FRT-flanked phleomycin/zeocin cassette was inserted at the end of the construct and was subsequently removed by a FLP plasmid.  The recombination cassette was inserted into the human CD34 locus obtained from a human PAC (P1 artificial chromosome) clone (88L2) expressing the entire human CD34 gene (160 kB insert) and 110 kb of the 5’ flanking region. The linearized construct was introduced by pronuclear injection into blastocysts from FVB/N mice. Mice from Dr. Tenen's colony at Harvard were transferred to the laboratory of Dr. Moore (Mt. Sinai) and were bred to C57BL/6J mice for at least 10 generations. Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes.

Allele

Symbol: Tg(CD34-tTA,-CD34)1Dgt
Name: transgene insertion 1, Daniel G Tenen
MGI accession ID: MGI:3776898
Generation method: Transgenic
Attributes: Inserted expressed sequence; Transactivator
Synonyms: CD34tTA
Marker symbol: Tg(CD34-tTA,-CD34)1Dgt
Marker name: transgene insertion 1, Daniel G Tenen
Marker synonyms: CD34tTA
Chromosome: UN
Strain of origin: FVB/N
Molecular note: 110 kb of human CD34 promoter sequence was placed upstream of a tTA tetracycline transactivator gene followed by an IRES domain and the coding genomic sequence for human CD34. Expression of both genes was detected in numerous tissues including heart and bone marrow.