These Wnt-7a knock-out mice exhibit ventralization of dorsal limb mesoderm tissues during development and thickening of dorsal limb dermus, loss of dorsal hair on digits and abnormal or missing posterior distal digits in mutant mice.
Andrew P McMahon, University of Southern California
Mice that are homozygous for the targeted mutation are viable, but sterile. A truncated mRNA transcript is detected during embryogenesis. Homozygotes exhibit ventralization of dorsal limb mesoderm tissues. The variable phenotype includes thickening of dorsal limb dermus, loss of dorsal hair on digits and abnormal or missing posterior distal digits. Abnormalities are more severe distally than proximally. Homozygous female mice have functioning ovaries, but are sterile due to abnormal development of the oviduct and uterus. Although homozygous male mice have normal spermatogenesis, Mullerian ducts do not regress resulting in blocked sperm passage. Mutant mice have reduced synapsin I levels and delayed synaptogenesis between cerebellar granule cells and mossy fiber neurons. This mutant mouse strain may be useful in studies related to dorsal-ventral and anterior-posterior patterning and axonal remodeling.
A targeting vector containing neomycin resistance and herpes simplex virus thymidine kinase genes was used to disrupt exon 2 of the targeted gene. The construct was electroporated into 129S1/Sv-p+ Tyr+ KitlSl-J/+ derived CJ7 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6J blastocysts.
|Allele Name||targeted mutation 1, Andrew P McMahon|
|Allele Type||Targeted (Null/Knockout)|
|Gene Symbol and Name||Wnt7a, wingless-type MMTV integration site family, member 7A|
|Strain of Origin||129S1/Sv-Oca2+ Tyr+ Kitl+|
|Molecular Note||A neomycin cassette was inserted into exon 2. Authors state that this is likely a null allele, but present no molecular evidence.|
|Mutations Made By|| |
Andrew McMahon, University of Southern California
The resulting mice were crossed at least once to C57BL/6 mice. The strain is maintained as a heterozygote. Homozygotes are viable but not fertile.
When using the Wnt-7a- mouse strain in a publication, please cite the originating article(s) and include JAX stock #004715 in your Materials and Methods section.