B6(Cg)-Snca^tm1.2Vlb/J

Stock number: 028559
Product name: Snca^Δflox, Snca KO
Strain synonyms: Snca delta flox (clean KO)
Research areas: Neurobiology Research, Research Tools

Description

These "Snca^Δflox" knock-out mice mutant mice lack the first coding exon (exon II) of the Snca (synuclein, alpha) gene. This strain may be useful in studies related to neurodegenerative synucleinopathies, such as Parkinson's disease and multiple system atrophy.

Detailed description

These "Snca^Δflox" knock-out mice mutant mice carry a 1164 bp fragment deletion containing the first coding exon (exon II) and adjacent flanking sequence of the Snca (synuclein, alpha) gene. Mice that are homozygous for the targeted mutation are viable and fertile. No ectopic sequences with exception of single loxP site at the position of the deleted fragment is present in the modified locus. No gene product (protein) is detected by Western blot analysis of neural tissue (cerebral cortex and midbrain) from homozygotes.



Mutations in human SNCA that result in aberrant polymerization and fibrillar aggregations are associated with neurodegenerative synucleinopathies, such as Parkinson's disease and multiple system atrophy.

Development

A targeting vector containing a FRT site-flanked NEO cassette and a loxP site was inserted downstream of exon II (the first coding exon) of the targeted Snca gene, and another loxP site was inserted upstream of exon II. This construct was electroporated into C57BL/6N-A^tm1Brd-derived JM8A3.N1 embryonic stem (ES) cells. The resulting chimeric animals were bred to C57BL/6J mice for 2 generations and then intercrossed to generate homozygotes. The homozygotes were crossed to transgenic mice (on a congenic C57BL/6 genetic background) expressing FLP recombinase under the control of the human ACTB promoter, generating Snca^floxΔneo mice. The FLP recombinase mediated excision of the FRT flanked NEO cassette and a 400 bp fragment encompassing a simple repeat region, which does not affect Snca locus expression. The Snca^floxΔneo mice that retained the floxed exon II were bred to C57BL/6J (Charles River) mice for 2 generations to remove the FLP recombinase transgene, before being intercrossed to generate homozygotes. These homozygous Snca^{floxΔneo/floxΔneo} mice were then bred to transgenic mice (on the C57BL/6 background) expressing Cre recombinase under the control of the CMV protomer (see, for example, Stock No. 006054) to excise the floxed exon II and flanking sequences. The resulting knock-out "Snca^Δflox" mice were then bred to C57BL/6J (Charles River) for 4 generations to to remove the Cre recombinase transgene, before being intercrossed to generate homozygotes. No ectopic sequences with exception of single loxP site at the position of the deleted fragment is present in the modified locus. Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

Allele

Symbol: Snca^tm1.2Vlb
Name: targeted mutation 1.2, Vladimir L Buchman
MGI accession ID: MGI:5700504
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Snca
Marker name: synuclein, alpha
Chromosome: 6
Strain of origin: C57BL/6N-A^tm1Brd
Molecular note: A targeting vector containing a FRT site-flanked neo cassette and a loxP site was inserted downstream of exon 2 (the first coding exon) of the targeted gene, and another loxP site was inserted upstream of exon 2. Flp-mediated recombination removed the FRT-flanked neo cassette leaving exon 2 floxed. Germline, Cre-mediated recombination removed exon 2. Western blot analysis of neural tissues confirmed that no protein is expressed.