STOCK Gba1^tm1Rlp Snca^tm1Nbm Tg(SNCA)1Nbm/Mmjax

Stock number: 027344
Product name: Gba^L444P; Snca^-; PAC-Tg(SNCA^WT)
Research areas: Neurobiology Research, Research Tools

Description

The PAC-Tg(SNCA^WT);Snca^-/-; Gba1^L444P/+ mice harbor a Snca knockout allele, a transgene encoding human alpha-synuclein and the L444P mutation in the Gba1 (glucosidase, beta, acid 1) gene associated with the alpha-synucleinopathy, Gaucher disease. This strain serves as an experimental control for STOCK Gba1^tm1Rlp Snca^tm1Nbm Tg(SNCA*A53T)1Nbm Tg(SNCA*A53T)2Nbm/Mmjax (MMRRC Stock Number 036733).

Detailed description

The PAC-Tg(SNCA^WT);Snca^-/-; Gba1^L444P/+ mice harbor a Snca knockout allele, a transgene encoding the human alpha-synuclein and the L444P mutation in the Gba1 (glucosidase, beta, acid 1) gene associated with the alpha-synucleinopathy, Gaucher disease. In mice homozygous for the transgene and the Snca KO, expression of endogenous mouse alpha-synuclein is abolished and replaced by human alpha-synuclein from two insertions of the PAC- Tg(SNCA^WT). The addition of the heterozygous Gaucher mutation, L444P, reduces glucocerebrosidase (GBA1) activity, reduces SNCA degradation, and results in the accumulation SNCA protein in culture. No apparent motor or enteric nervous system dysfunction is observed. The enzyme GBA1 is involved in lysosomal protein degradation and thus in the lysosomal-autophagy pathway mainly responsible for SNCA degradation. Heterozygous carriers of Gaucher disease have an increased risk for Parkinson’s disease. This strain serves as an experimental control for STOCK Gba1^tm1Rlp Snca^tm1Nbm Tg(SNCA*A53T)1Nbm Tg(SNCA*A53T)2Nbm/Mmjax (MMRRC Stock Number 037633), a combined model of Parkinson’s and Gaucher disease that results in an exacerbation of the motor and gastrointestinal deficits found in the Parkinson’s A53T model.

Development

The PAC-Tg(SNCA^WT) transgene was designed using the 146 kb RPCI-1 human male P1 artificial chromosome (PAC) clone 27M07, containing the entire human SNCA (synuclein, alpha (non A4 component of amyloid precursor)) gene. This transgene was microinjected into the pronuclei of fertilized FVB/N ova. Founder mice were bred to FVB/N wildtype mice.

The targeting vector for the Snca knockout allele was designed to replace exons 4 and 5 with a reverse-oriented neomycin resistance cassette. The construct was electroporated into 129S6/SvEvTac-derived TC-1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts and the resulting chimeric mice were crossed to 129S6/SvEvTac.

The transgenic PAC-Tg(SNCA^WT) strain and the Snca-/- strain were combined to form a homozygous transgenic, homozygous Scna KO strain maintained on a mixed FVB/N;129S6/SvEvTac background. The double mutant is distributed by The Jackson Laboratory as Stock No. 010710).

The targeting vector for the Gba1 L444P knockin allele was designed to insert a proline to leucine substitution mutation at amino acid position 444 in exon 10. The construct was electroporated into 129S4/SvJae-derived J1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts and the resulting chimeric mice were crossed to C57BL/6. The Gba1^L444P mutant is distributed by MMRRC as Stock No. 000117. The double SCNA mutant was crossed to Gba1^L444P mice and a colony was generated by random intrastrain matings that is homozygous for the SNCA transgene and the Scna KO and heterozygous for the Gba1^L444P allele.

Allele

Symbol: Tg(SNCA)1Nbm
Name: transgene insertion 1, Robert L Nussbaum
MGI accession ID: MGI:4412055
Generation method: Transgenic
Attributes: Inserted expressed sequence; Humanized sequence
Synonyms: hSNCA^WT; PAC-Tg(SNCA^WT)
Marker symbol: Tg(SNCA)1Nbm
Marker name: transgene insertion 1, Robert L Nussbaum
Marker synonyms: PAC-Tg(SCNA^WT)
Chromosome: UN
Strain of origin: FVB/N
Expressed genes: SNCA,synuclein alpha,human
Molecular note: To generate the PAC-Tg(SNCAWT) transgene, the 146 kb RPCI-1 human male P1 artificial chromosome (PAC) clone 27M07, containing the entire human SNCA (synuclein, alpha (non A4 component of amyloid precursor)) gene and 34 kb of its upstream region, was used. This transgene was microinjected into the pronuclei of fertilized FVB/N ova. The only transgenic founder shown to contain the complete SNCA gene was bred to FVB/N wildtype mice.

Allele

Symbol: Gba1^tm1Rlp
Name: targeted mutation 1, Richard L Proia
MGI accession ID: MGI:2180202
Generation method: Targeted
Attributes: Hypomorph; Humanized sequence
Synonyms: Gba^L444P; L444P
Marker symbol: Gba1
Marker name: glucosylceramidase beta 1
Marker synonyms: betaGC; GBA; GBA1; GC; GCase; GCB; GLUC; glucocerebrosidase
Chromosome: 3
Strain of origin: 129S4/SvJae
Molecular note: A leucine to proline substitution mutation at amino acid position 462 (444 in mature protein) (p.L462P) is associated with Gaucher disease type 3 in humans. This mutation was introduced in mice using a single insertion mutagenesis procedure, changing leucine codon 462 (TTG) to proline (CCG). The level of gene expression in brain of mutant mice is similar to wild-type as determined by Northern blot analysis, but enzyme assays with liver, brain, and skin extracts demonstrate that enzyme activity is 20% that of wild-type.

Allele

Symbol: Snca^tm1Nbm
Name: targeted mutation 1, Robert L Nussbaum
MGI accession ID: MGI:2389489
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: Scna-; Snca^-
Marker symbol: Snca
Marker name: synuclein, alpha
Marker synonyms: alphaSYN; alpha-Syn; alpha-synuclein; NACP; PARK1; PARK4; PD1
Chromosome: 6
Strain of origin: 129S6/SvEvTac
Molecular note: Exons 4 and 5 were replaced with a neomycin selection cassette inserted by homologous recombination. While the separation of Western blot results by 2D-PAGE showed various isoforms in total brain extract obtained from wild-type mice, protein was undetected in samples obtained from homozygous mutant mice.