B6;D2-Tg(MMTVTGFB1)46Hlm/J

Stock number: 002375
Product name: MMTV-TGF-β1^S223/225

Description

These MMTV-TGF-β1^S223/225 mice contain a transgene consisting of a modified allele of simian transforming growth factor, beta 1 that is expressed in mammary epithelium.

Detailed description

Mice carrying the (MMTVTGFB1)46Hlm transgene are viable, fertile, and able to lactate through multiple litters. The transgene is expressed in mammary epithelium of 13-week virgin as well as lactating animals. Expression was localized to ductal epithelium. Expression in salivary gland was also detected. Ductal development was markedly inhibited in virgin transgenic mice by 13 weeks. The effect on lateral branching was more severe in homozygous mice carrying 4 copies of the transgene. Epithelial proliferation as measured by BrdU labeling index was markedly reduced. Mammary glands from pregnant and lactating mice showed fully developed lobules, although transgenic mice had fewer lobules. No mammary tumors were found in transgenic mice followed for over 300 days. Offspring of crosses between transgenic mice overexpressing TGFA (which develop mammary carcinoma) and the TGFB1 transgenic mice also were free of mammary carcinoma.

Development

The MMTV-TGFb1S223/225 construct was prepared by replacing the SV40 early promoter in the pKCR vector with the complete MMTV-LTR. 1.4-kb of simian transforming growth factor, beta 1 cDNA was altered to change cysteine to serine at positions 223 and 225 (S223C/S225C) and inserted into the EcoRI site of rabbit β-globin exon 3. The transgene was injected into the pronuclei of B6D2F2 mouse oocytes. Mice from founder line 46 were bred with B6D2F1 mice to establish the colony.

Allele

Symbol: Tg(MMTVTGFB1)46Hlm
Name: transgene insertion 46, Harold L Moses
MGI accession ID: MGI:3040376
Generation method: Transgenic
Attributes: Inserted expressed sequence
Marker symbol: Tg(MMTVTGFB1)46Hlm
Marker name: transgene insertion 46, Harold L Moses
Chromosome: UN
Strain of origin: (C57BL/6 x DBA/2)F2
Expressed genes: TGFB1,transforming growth factor-beta 1,simian
Molecular note: This transgene contains the mouse mammary tumor virus promoter and a modified allele of simian transforming growth factor, beta 1. In this modified allele cystein codons at positions 223 and 225 were changed to serine codons (this generates an active form of TGFB1). The construct also contained exons 2 and 3 of the rabbit beta-globin gene.