B6.Cg-Tg(Vil1-EGFP)106Gum/J

Stock number: 028353
Product name: 12.4KVil-EGFP
Research areas: Cancer Research, Internal/Organ Research, Research Tools

Description

12.4KVil-EGFP transgenic mice have the 12.4 kbp mouse villin 1 promoter directing expression of EGFP to villus and crypt epithelial cells, along the entire small intestine and colon, in a cephalocaudal gradient expression pattern similar to endogenous Vil1. These mice may be useful in studying intestinal organogenesis, gastric stem cell biology and cancer.

Detailed description

12.4KVil-EGFP transgenic mice have the 12.4 kbp mouse villin 1 promoter directing expression of EGFP to villus and crypt epithelial cells, along the entire small intestine and colon. The donating investigator reports the expression pattern is specific and can be visualized by direct fluorescence in live tissues.

This 12.4KVil-EGFP transgenic line has the highest intensity of EGFP expression in the duodenum with progressively diminished expression in the ileum and colon. This decreasing cephalocaudal gradient of expression closely resembles that of endogenous villin in the intestine. EGFP is expressed in all epithelial cells throughout the small and large intestine, with no reported evidence of mottled or variegated expression.

EGFP expression is appropriately abrupt at the pyloric border (discrete epithelial border between stomach and intestine). No reporter expression is observed in the yolk sac or the majority of the stomach (but adjacent intestinal cells intensely express EGFP). Expression is observed in a rare subpopulation of gastric epithelial progenitor cells (GPCs) that multiply in response to IFNγ.

Transgene expression is first detectable in the early stages of intestinal organogenesis (embryonic midgut and hindgut at 12.5 dpc); this precedes the major morphological remodeling of the intestinal epithelium (14-15 dpc).

Overall, the donating investigator reports that the 12.4KVil-EGFP expression matches that of their 12.4KVil-Cre transgenic lines 997 and 1000 (Stock Nos. 004586 and 021504, respectively). Whereas both 12.4KVil-Cre lines 997 and 1000 are reported to have a small amount of mosaic expression in colon and the 12.4KVil-Cre line 997 has a very low level of cre activity in testes (<1%), these 12.4KVil-EGFP mice have not been specifically characterized regarding colonic mosaicism or germline EGFP expression to date (April 2016).

Both hemizygous and homozygous 12.4KVil-EGFP transgenic mice are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. The strain donor reports that EGFP expression is more intense in mice homozygous for the 12.4KVil-EGFP transgene compared to mice hemizygous for the 12.4KVil-EGFP transgene.

Development

The 12.4KbVilEGFP transgene (12.4KVil-EGFP) was designed by Dr. Deborah L. Gumucio (University of Michigan) to have the 12.4 kbp promoter fragment from the mouse villin 1 gene (Vil1) with an enhanced green fluorescent protein coding sequence (EGFP). This transgene was injected into the pronuclei of fertilized (C57BL/6 x SJL)F2 mouse eggs. Founder animals were bred to C57BL/6NCrl mice for germline transmission. Founder line 106 was found to have the strongest expression. The donating investigator reports that 12.4KVil-EGFP mice from this founder line were subsequently backcrossed to C57BL/6NCrl mice for at least ten generations prior to sending hemizygous males with black coat color to The Jackson Laboratory in 2016 (see SNP results below). Upon arrival, sperm was cryopreserved.

Of note, it is not known if the Y chromosome has been fixed to the C57BL/6 background during backcrossing.

In 2016, a 32 SNP (single nucleotide polymorphism) panel analysis, with 27 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 males sent to The Jackson Laboratory Repository. While the 27 markers throughout the genome suggested a C57BL/6 genetic background, 4/5 or 5/5 of the markers that determine C57BL/6J from C57BL/6N were found to be segregating in all mice (chromosomes 8 [~15.2 Mbp], 11 [~4.4 Mbp], 13 [~41.0 Mbp], 15 [~57.6 Mbp] and 19 [~49.9 Mbp]). These data suggest that the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6J;C57BL/6N genetic background.

Allele

Symbol: Tg(Vil1-EGFP)106Gum
Name: transgene insertion 106, Deborah L Gumucio
MGI accession ID: MGI:5763081
Generation method: Transgenic
Attributes: Reporter
Synonyms: 12.4KVil-EGFP
Marker symbol: Tg(Vil1-EGFP)106Gum
Marker name: transgene insertion 106, Deborah L Gumucio
Chromosome: UN
Strain of origin: (C57BL/6 x SJL)F2
Expressed genes: GFP,Green Fluorescent Protein,
Site of expression: EGFP is expressed in all epithelial cells throughout the small and large intestine.
Molecular note: The transgene was designed to have the 12.4 kbp promoter fragment from the mouse villin 1 gene (Vil1) with an enhanced green fluorescent protein coding sequence (EGFP). This transgenic founder line 106 has the highest intensity of EGFP expression in the duodenum with progressively diminished expression in the ileum and colon. EGFP is expressed in all epithelial cells throughout the small and large intestine, with no reported evidence of mottled or variegated expression.