This Rxra knockout strain is useful in studies of cardiac development, and the role of retinoic acid receptors in cellular processes.
Henry Sucov, Medical University of South Carolina
The Rxra, retinoid X receptor alpha, gene encodes for a nuclear receptor of retinoic acid. The retinoid X receptors regulate gene expression via both ligand-dependent and ligand-independent mechanisms. These mice carry a targeted mutation for the Rxra gene in which a NEO cassette replaced part of exon 3 and intron 3. Mice that are heterozygous for the targeted mutation are viable and fertile. Homozygous null mice have an embryonic lethal phenotype, failing to develop past embryonic day 15.5 due to congestive heart failure. Abberant non-functional gene product (mRNA) is detected by Northern analysis of homozygous embryos, embryonic day 13.5. Homozygous embryos exhibit impaired placental, eye, cardiac and hepatic (transient delay in fetal erythropopiesis) development as well as subdermal edema. Heterozygotes exhibit cardiac and myocardial defects.
A targeting vector containing PGK-NEO cassette was used to disrupt part of exon 3 and intron 3. The construct was electroporated into 129S4/SvJae derived J1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts. The resulting chimeric animals were crossed to C57BL/6 mice. The mice are on a STOCK background that includes C57BL/6, ICR (CD-1), 129, and other backgrounds. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) at least once to establish the colony.
|Allele Name||targeted mutation 1, Ronald M Evans|
|Allele Type||Targeted (Null/Knockout)|
|Gene Symbol and Name||Rxra, retinoid X receptor alpha|
|Strain of Origin||129S4/SvJae|
|Molecular Note||A genomic fragment containing part of exon 3 and intron 3 was replaced with a neomycin resistance cassette. RT-PCR analysis on RNA derived from E13.5 embryos indicated that no normal transcript was produced from this allele in homozygous embryos.|
When maintaining a live colony, heterozygous mice may be bred together, to wildtype siblings, or to C57BL/6J inbred mice (Stock No. 000664). Homozygotes are not viable.
When using the RXRalpha- mouse strain in a publication, please cite the originating article(s) and include JAX stock #024089 in your Materials and Methods section.