B6.129S-Fn1^tm1Hyn/2J

Stock number: 008445
Research areas: Cardiovascular Research, Developmental Biology Research

Description

These mice, carrying a targeted mutation of the fibronectin 1 gene (Fn1), have been used in a search for cardiac development modifier genes demonstrating phenotypic differences on C57BL/6J and 129S4/SvJae genetic backgrounds (Astrof 2007). On the C57BL/6J genetic background, cardiac development progresses further than that of 129S4 background mice, and results in a centrally-positioned looped heart. This strain may be helpful in studies of cardiac development.

Detailed description

These mice carry a targeted mutation in the fibronectin 1 gene identical to that found in Stock No. 002270.

This line, backcrossed more than 13 times to C57BL/6J in the donating investigator's colony, has been used in a search for cardiac development modifier genes demonstrating phenotypic differences on C57BL/6J and 129S4/SvJae genetic backgrounds (Astrof, 2007).

In the majority of 129S4 background homozygous targeted mutant embryos, heart progenitors remain at their anterior bilateral positions and fail to fuse at the midline to form a heart tube. However, on the C57BL/6J genetic background, cardiac development progresses further and results in a centrally-positioned looped heart.

Linkage analysis led to the identification of a 1-Mbp interval on mouse Chromosome 4 containing 21 genes, including five that are differentially expressed between C57BL/6J and 129S4/SvJae.

This strain may be helpful in studies of cardiac development.

Development

A PGK-neomycin resistance cassette replaced 0.8 kb of the targeted gene including the translation initiation site and part of the signal sequence. This mutation was created in 129S2/SvPas-derived D3 embryonic stem (ES) cells. The mice were bred to 129S4/SvJae then backcrossed to C57BL/6J in the donating investigator's colony for at least 13 generations. The strain was sperm-cryopreserved and will typically be recovered using C57BL/6J females maintained at The Jackson Laboratory.

Allele

Symbol: Fn1^tm1Hyn
Name: targeted mutation 1, Richard Hynes
MGI accession ID: MGI:1857170
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Fn1
Marker name: fibronectin 1
Chromosome: 1
Strain of origin: 129S2/SvPas
Molecular note: A PGK-neomycin resistance cassette replaced 0.8 kb of the gene including the translation initiation site and part of the signaling sequence. Plasma concentrations of fibronectin in heterozygotes were one-half those of wild-type littermates. The encoded protein was not detectable in immunoprecipitations from cultures of homozygous mutant E7.5 embryos.