C57BL/6N-Gba1^tm1.1Mjff/J

Stock number: 019106
Product name: Gba D409V KI
Strain synonyms: Gba^{tm2636(D427V)Arte}
Research areas: Neurobiology Research, Research Tools

Description

These mice express the mutant D409V GBA1 protein and possess loxP sites flanking exons 6 through 8 of the Gba1 (glucosidase, beta, acid 1) gene. They have applications in studies related to Parkinson's disease, Gaucher disease and synucleinopathies.

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 mice express the mutant D427V Gba1 protein, which corresponds to the D409V mutation in the mature human GBA1 protein, and possess loxP sites flanking exons 6 through 8. Mice that are heterozygous for the targeted mutation are viable and fertile. Homozygous Gba1 D409V knock-in mice show a significant reduction in Gba1 protein level and glucocerebrosidase activity, and a significant increase in glucosylsphingosine in both brain and liver tissues.

Heterozygotes demonstrate significant cognitive impairment by the age of 12 months, as determined by both Morris water maze and Y-maze behavioral tests (PMID: 31299418).

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.

Preliminary characterization was presented in a poster at the 2015 Society for Neuroscience conference.

Development

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. 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. 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 (see SNP results below). These mice no longer carry the FLP recombinase allele. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6N (Stock No. 005304) at least once to establish the colony.

A 32 SNP (single nucleotide polymorphism) panel analysis, with 27 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. While the 27 markers throughout the genome suggested a C57BL/6 genetic background, 4 of 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6J ; C57BL/6N 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.