C57BL/6-Gba1^tm1.1Mjff Tg(Thy1-SNCA)15Mjff/J

Stock number: 029124
Product name: GBA1 D409V KI x mThy1-hSNCA
Research areas: Neurobiology Research

Description

These mice carry the Gba1^tm1.1Mjff allele (Stock No. 019106) and the Tg(Thy1-SNCA)15Mjff transgene (Stock No. 017682). They have applications related to Parkinson's disease, Gaucher disease and synucleinopathies, and neurodegeneration elicited by the aggregation of SNCA. While increased SCNA pathology and grip strength reductions are observed in this model, the nigrostriatal system remains largely intact. Neuroinflammation is not exacerbated by the GBA D409V mutation.

Detailed description

Mutations in human GBA1 (glucosidase, beta, acid 1) can cause Gaucher disease, an autosomal recessive lysosomal (lipid) storage disease, and have been associated with late onset Parkinson's disease and Lewy body dementia.

These GBA1 D409V KI x mThy1-hSNCA mice express a transgene containing human SNCA (synuclein, alpha; also called aSyn) under the direction of a mouse Thy1 (thymus cell antigen 1, theta) promoter, and the mutant mouse D427V GBA1 protein, which corresponds to the D409V mutation in the mature protein.

While increased SCNA/aSyn pathology and grip strength reductions are observed in mice homozygous for Gba1^tm1.1Mjff and hemizygous for Tg(Thy1-SNCA)15Mjff, the nigrostriatal system remains largely intact. Increases in aSyn pathology in the GBA1 D409V KI x mThy1-hSNCA mouse are most striking in the hippocampus and substantia nigra, with more subtle increases in pS129 (phosphoserine 129) aSyn in the cortex and striatum. Neuroinflammation is not exacerbated by the GBA1 D409V mutation. GBA1 D409V KI x mThy1-hSNCA mice display normal dopamine levels at 4, 8, and 12 months of age.

In addition, these mice possess loxP sites flanking exons 6 through 8 of the Gba1 gene. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exons 6 through 8 deleted in the cre-expressing tissues and will no longer express the mutant D427V protein.

Mice that are homozygous for the Gba1^tm1.1Mjff allele and hemizygous for the Tg(Thy1-SNCA)15Mjff transgene are viable and fertile.

Development

Mice carrying the Gba1^tm1.1Mjff allele (Stock No. 019106) were bred to mice carrying the Tg(Thy1-SNCA)15Mjff transgene (Stock No. 017682) to generate this GBA1 D409V KI x mThy1-hSNCA double mutant line.

For the Gba1^tm1.1Mjff allele, a targeting vector containing a FRT-flanked NEO cassette, and a F3 FRT-flanked PurO cassette was used to introduce the D427V point mutation into exon 10. The FRT-flanked NEO cassette was inserted into intron 5 and the F3 FRT-flanked PurO cassette was inserted into intron 8. In addition, loxP sites were inserted to flank exons 6 through 8. The construct was electroporated into C57BL/6NTac derived Art B6 3.6 embryonic stem (ES) cells. Correctly targeted ES cells were injected into BALB/c blastocysts. The resulting chimeric animals were crossed to FLP recombinase expressing females on the C57BL/6NTac background, C57BL/6NTac-Tg(CAG-Flpe)2Art, to remove the selection cassettes. These mice no longer carry the FLP recombinase allele. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6NJ (Stock No. 005304) at least once to establish the colony.

The mThy1-hSNCA transgene consists of the human a-synuclein (SNCA) gene driven by a mouse thymus cell antigen 1 (Thy-1) promoter. The construct was microinjected into fertilized C57BL/6NTac oocytes and males from founder line 15 were bred to C57BL/6NTac females to establish the colony. Upon arrival at The Jackson Laboratory, mice were bred to C57BL/6NJ inbred mice (Stock No. 005304) for at least one generation.

In 2020, a 48 SNP (single nucleotide polymorphism) panel analysis, with 43 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6J and C57BL/6N substrains, was performed on the rederived living colony at The Jackson Laboratory Repository. One of the 5 markers that determine C57BL/6J from C57BL/6N was found to be segregating on Chromosome 6. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6N;C57BL/6J genetic background.

Allele

Symbol: Gba1^tm1.1Mjff
Name: targeted mutation 1.1, The Michael J Fox Foundation
MGI accession ID: MGI:5461046
Generation method: Targeted
Attributes: Humanized sequence; Not Specified
Synonyms: Gba^{tm1(D427V)Mjff}; Gba1^D409V
Marker symbol: Gba1
Marker name: glucosylceramidase beta 1
Marker synonyms: betaGC; GBA; GBA1; GC; GCase; GCB; GLUC; glucocerebrosidase
Chromosome: 3
Strain of origin: C57BL/6NTac
Molecular note: A targeting vector containing a FRT site flanked NEO cassette, and a F3 FRT site flanked PurO cassette was used to introduce the D427V point mutation into exon 10. D427V corresponds to the human D409V mutation. The FRT site flanked NEO cassette was inserted into intron 5 and the F3 FRT site flanked PurO cassette was inserted into intron 8. In addition, loxP sites were inserted to flank exons 6 through 8. Flp-mediated recombination removed the neo cassette.

Allele

Symbol: Tg(Thy1-SNCA)15Mjff
Name: transgene insertion 15, The Michael J Fox Foundation
MGI accession ID: MGI:5308782
Generation method: Transgenic
Attributes: Inserted expressed sequence; Humanized sequence
Synonyms: Tg(Thy1-SNCA)15Youy; Thy-1-SNCA
Marker symbol: Tg(Thy1-SNCA)15Mjff
Marker name: transgene insertion 15, The Michael J Fox Foundation
Chromosome: 11
Strain of origin: C57BL/6NTac
Expressed genes: SNCA,synuclein alpha,human
Molecular note: The transgene consists of the human alpha-synuclein (SNCA) gene driven by a mouse thymus cell antigen 1 (Thy-1) promoter. Line 15 was generated. Transgene insertion occurred on Chr 11, causing a 38 Kb deletion.