B6.Cg-Tg(MMTVtTA)1Mam/J

Stock number: 002618
Product name: MMTV-tTA
Research areas: Research Tools

Description

These MMTV-tTA mice contain the tetracycline-controlled transactivator protein (tTA) and can be used to target expression of tTA to the epithelial cells of secretory organs and skin in transgenic mice.

Detailed description

The MMTV-LTR was used to target expression of tetracycline-controlled transactivator protein (tTA) to the epithelial cells of secretory organs and skin in transgenic mice. When Tg(MMTVtTA)1Mam transgenic mice were mated to a second transgenic strains carrying either lacZ or luciferase reporter genes coupled to tetracycline-responsive promoter elements (TRE; tetO), nearly uniform expression of the reporter was found in seminal vesicle, salivary gland, and Leydig cells of the double transgenic offspring. More heterogeneous reporter gene expression patterns were observed in mammary epithelial cells and basal cells of the epidermis. Lower reporter gene expression levels also were observed in a broad range of tissues. Transcriptional activation mediated by tTA was up to several hundred-fold and was abrogated after the administration of tetracycline. MMTV-tTA transgenic mice may be useful in experiments examining the roles of biological factors at defined developmental stages in the epithelial cells of salivary gland, seminal vesicle, mammary gland, and skin and in the Leydig cells of testes.

Development

This strain was developed in the laboratory of Dr. Lothar Hennighausen at the National Institute of Diabetes, Digestive, & Kidney Diseases, National Institutes of Health. While the primary publication does not define the genetic background(s) used in generating these transgenic mice, correspondence with the donating investigator (in 1996) indicates that the transgene was introduced into a "B6/SJL" genetic background and was backcrossed four generations to B6 prior to arrival at The Jackson Laboratory. Upon arrival, mutant mice were backcrossed to C57BL/6J for at least one additional generation.

Allele

Symbol: Tg(MMTVtTA)1Mam
Name: transgene insertion 1, Lothar Hennighausen
MGI accession ID: MGI:3053958
Generation method: Transgenic
Attributes: Transactivator
Marker symbol: Tg(MMTVtTA)1Mam
Marker name: transgene insertion 1, Lothar Hennighausen
Chromosome: UN
Strain of origin: C57BL/6 and SJL
Expressed genes: tTA,tetracycline-controlled transactivator,E. coli
Site of expression: Expresses tTA in the epithelial cells of secretory organs and skin. When mated to a tetop-lacz reporter mouse, nearly uniform expression of lacZ was found in seminal vesicle, salivary gland, and Leydig cells. More heterogeneous patterns of lacZ expression were observed in mammary epithelial cells of the epidermis.
Molecular note: The MMTV LTR was used to target expression of tetracycline-controlled transactivator protein (tTA) to the epithelial cells of secretory organs and skin. The tetracycline resistance gene (TetR) was fused at the C-terminus with the viral co-activator, virion protein 16 of the herpes simplex virus (VP-16).
General note: Additional lines were generated and showed comparable tissue expression patterns.

When transgenic mice were mated to mice transgenic for either lacZ or luciferase reporter genes coupled to tetracycline-responsive promoter elements (TRE), nearly uniform expression of the reporter was found in seminal vesicle, salivary gland, and Leydig cells of the double transgenic offspring. More heterogeneous patterns of reporter expression were observed in mammary epithelial cells and basal cells of the epidermis. Lower levels of reporter gene expression were also observed in a broad range of tissues. Transcriptional activation mediated by tTA was up to several hundredfold and was abrogated after the administration of tetracycline.

In combination with Tg(BCR/ABL1)2Dgt, when tetracycline administration is stopped, bitransgenic mice are models for B cell acute lymphoblastic leukemia (ALL). (J:72377)