B6.FVB-Tg(Fabp4-lacZ)4Mosh/J

Stock number: 018625
Research areas: Cardiovascular Research, Research Tools

Description

This XlacZ4 transgenic line expresses lacZ under the direction of the mouse Fabp4 promoter with beta-galactosidase activity detected in vascular smooth muscle cells and pericytes. This strain would be useful as a marker for vascular smooth muscle cells and pericytes.

Detailed description

These transgenic mice express beta-galactosidase under the direction of the mouse Fabp4, fatty acid binding protein 4, adipocyte, (aP2) promoter. Beta-galactosidase activity is detected in transgenic embryos as early as 9.0 dpc in facial and eye ectoderm cells of the ventral region of brachial somites, and at age 10.5 dpc in myogenic cells, thymic epithelial precursors and nasal epithelium. In later stage embryos and in adult transgenic mice, beta-galactosidase activity is detected in the nuclei of vascular smooth muscle cells and pericytes (mural cells) of tissues such as the retina and skeletal muscle. No transgene expression is detected in major elastic arteries. For example, vascular smooth muscle cells of the coronary arteries from the proepicardial organ and intercostal arteries express the transgene, while the vascular smooth muscle cells of the ascending aorta and thoracic aorta do not. Transgene expression is not detected in skeletal and smooth muscles, the hepatic vascular bed and liver. During blood vessel injury, transgene expression is deactivated and is reactivated during would healing (formation of neointima thickening). Mice that are homozygous for the transgenic insert are viable and fertile. Preliminary results indicate that transgene expression in vascular smooth muscle cells could be driven by the 7.4 kb of upstream sequences of the promoter that is included in the transgenic construct.

In an attempt to offer alleles on well-characterized or multiple genetic backgrounds, alleles are frequently moved to a genetic background different from that on which an allele was first characterized. This is the case for the strain above. It should be noted that the phenotype could vary from that originally described. We will modify the strain description if necessary as published results become available.

Development

A transgenic construct containing a beta-galactosidase gene (lacZ) with a SV40 nuclear localization signal, under the control of the mouse Fabp4, fatty acid binding protein 4, adipocyte, (aP2) promoter, was injected into fertilized FVB/N mouse eggs. Founder line 4 was subsequently established. A single copy of the transgene integrated into the central region of chromosome 19. The donating investigator reports that these mice were then backcrossed to C57BL/6 for 10 generations (see SNP notes below). Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) at least once to establish the colony.

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 rederived living colony at The Jackson Laboratory Repository. While the 27 markers throughout the genome suggested a C57BL/6 genetic background, 4 of 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6J ; C57BL/6N genetic background.

Allele

Symbol: Tg(Fabp4-lacZ)4Mosh
Name: transgene insertion 4, Moshe Shani
MGI accession ID: MGI:4849449
Generation method: Transgenic
Attributes: Reporter
Synonyms: XLacZ4; X-lacZ4
Marker symbol: Tg(Fabp4-lacZ)4Mosh
Marker name: transgene insertion 4, Moshe Shani
Chromosome: 19
Strain of origin: FVB/N
Expressed genes: lacZ,beta-galactosidase,E. coli
Site of expression: Beta-galactosidase activity is detected in transgenic embryos as early as 9.0 dpc in facial and eye ectoderm cells of the ventral region of brachial somites, and at age 10.5 dpc in myogenic cells, thymic epithelial precursors and nasal epithelium. In later stage embryos and in adult transgenic mice, beta-galactosidase activity is detected in vascular smooth muscle cells and pericytes (mural cells).
Molecular note: The mouse promoter drives adipose-specific expression of the lacZ gene with a nuclear localization sequence. Line 4 contains a single copy of the transgene. Expression is observed in vascular smooth muscle cells through out the vascular bed, with the exception of the major elastic arteries, and in pericytes.