STOCK Tg(tetO-Ipf1,EGFP)956.6Macd/J

Stock number: 005699
Product name: Tg^Pdx1
Research areas: Endocrine Deficiency Research, Metabolism Research, Research Tools, Sensorineural Research

Description

These Tg^Pdx1 mice express a transgene containing EGFP and Ipf1 after crossing with a strain expressing tetracycline-transactivator (tTA) under the control of a tissue-specific promoter. Such double mutant mice may be useful in studies of pancreatic endocrine/exocrine function and diabetes.

Detailed description

Mice hemizygous for the transgene are viable, fertile, normal in size, and do not display any behavioral abnormalities. At the Jackson Laboratory, no homozygous mice were produced from mating hemizygotes together, suggesting that homozygous transgenic animals die in utero. Expression of the bicistronic transgene is under the regulation of a tetracycline promoter element (TRE; tetO). By themselves, these transgenic mice do not express EGFP, but when these mice are mated with a second transgenic strain expressing tetracycline-transactivator (tTA) protein under the control of a tissue-specific promoter, Ipf1 and EGFP are highly expressed in the appropriate tissue of bitransgenic offspring.

This mouse was originally designed to be mated to an apancreatic targeted mutant with tTA_off in place of the endogenous Ipf1 gene (see Stock No. 005701). The combined mutations allow normal pancreatic development and function until doxycycline treatment renders the double mutant mouse conditionally null for Ipf1 expression. Using these double transgenic mice, pancreatic developmental can be arrested at any stage during embryonic development or in adult mice. Such double mutant mice may be useful in studies of pancreatic endocrine/exocrine function and diabetes. Tg(tetO-Ipf1,EGFP)956.6Macd transgenic mice also may be bred with other tTA transgenic strains for conditional mutation analysis.

Development

A bicistronic transgenic vector was generated containing an Ipf1 minigene (both exons linked with a shortened intron and preceded by a truncated 5' untranslated region) and an internal ribosome entry site-linked enhanced green fluorescent protein (EGFP) all under transcriptional control of a tetracycline-responsive regulatory element (TRE). Transgenic mice were generated by pronuclear injection of the construct into fertilized [C57BL/6 x SJL] F2 hybrid embryos. Two-cell stage eggs were implanted into pseudopregnant foster mothers. Founder line 956.6 was obtained and was maintained by transgenic positive sibling intercross. At some point, transgenic mice were bred to B6;129 mice with a targeted mutation. The targeted mutation was selected against in subsequent breedings, and the transgenic line was again maintained by hemizygous intercrosses prior to cryopreservation.

Allele

Symbol: Tg(tetO-Ipf1,EGFP)956.6Macd
Name: transgene insertion 956-6, Raymond J MacDonald
MGI accession ID: MGI:3655514
Generation method: Transgenic
Attributes: Reporter; Inducible; Inserted expressed sequence
Marker symbol: Tg(tetO-Ipf1,EGFP)956.6Macd
Marker name: transgene insertion 956-6, Raymond J MacDonald
Chromosome: UN
Strain of origin: (C57BL/6 x SJL)F2
Expressed genes: GFP,Green Fluorescent Protein,
Site of expression: Transgenic mice do not express EGFP until a tetracycline-transactivator (tTA) protein is introduced; after which point Ipf1 and EGFP from the transgene are highly expressed. Transgenic mice have low level transgene expression (mRNA) in liver, kidney, spleen, and salivary gland.
Molecular note: A transgenic vector containing an Ipf1 minigene (both exons of Ipf1 linked by a shortened exon and preceded by a truncated 5' UTR and an IRES-linked EGFP reporter) under control of seven direct repeats of the tetracycline operator (tetO) fused to the human cytomegalovirus (hCMV) immediate early promoter. High expression of Ipf1 and EGFP is induced by the introduction of the tetracycline-transactivator protein by breeding with an appropriate mouse line.

Allele

Symbol: Gnat2^cpfl3
Name: cone photoreceptor function loss 3
MGI accession ID: MGI:3588845
Generation method: Spontaneous
Marker symbol: Gnat2
Marker name: guanine nucleotide binding protein, alpha transducing 2
Chromosome: 3
Strain of origin: various
Molecular note: A single nucleotide substitution of G to A at coding nucleotide 598 in exon 6. This mutation converts codon 200 from aspartic acid to asparagine (p.D200N).
General note: This allele has been detected in the following strains either by genotyping or complementation testing: ALS/LtJ, SENCARA/PtJ, SENCARB/PtJ, SENCARC/PtJ, PN/nBSwUmabJ. (J:122428) The allele has also been reported in NMRI and CD1 (Lluis Montoliu, J:212307)