These Gba*L444P mice contain a mutation in the Gba gene, similar to that found in humans with Gaucher disease and Parkinson's disease.
Dr. Edward Ginns, University of Massachusetts Medical School
These Gba*L444P mice contain the mutation L444P in exon 10 of the glucosidase, beta, acid (Gba) gene. This mutation introduces a leucine to proline mutation analogous to a common Gba mutation found in humans with the α-synucleinopathy Gaucher disease. In Gaucher disease, mutations of the lysosomal enzyme GBA prevents the degradation of its substrate, glucocerebroside, into ceramide and glucose, resulting in an accumulation of glucocerebroside within lysosomes mainly in macrophages. These lipid-filled mutant macrophages contribute to the enlargement of the spleen and liver, damage to blood-forming tissues, bone fractures and pain, and damage to the lungs and nervous tissues. Gaucher disease is rare, but is more prevalent among individuals of Ashkenazi Jewish descent. Carriers of GBA mutations often have a higher genetic risk of developing Parkinson's disease and Lewy body.
Homozygous Gba*L444P mice are viable and fertile. The L444P mutation is associated with severe type 2 or 3 neuronopathic Gaucher disease characterized by very early onset of major visceral and progressive CNS disease seen extensively in the Swedish Norbottnian population. The Gba enzyme activity in liver and spleen was 21% and 32% of the Gba enzyme activity in normal, respectively. Gba activity levels in brain were 35% of wildtype. Enhanced α-syn accumulation and astroglial activation are apparent in the nigrostriatal pathway of these mice. These are relevant for the study of Gaucher and Parkinson's disease.
A targeting construct was designed to insert a loxP-flanked neomycin (neo) resistance cassette, in opposite orientation to the gene, downstream of the coding region of the glucosidase, beta, acid (Gba) gene. A point mutation was introduced in exon 10, resulting in a leucine to proline mutation, L444P, commonly found in humans carrying Gaucher disease. This targeting construct was electroporated into 129X1/SvJ-derived RW4 embryonic stem (ES) cells and correctly targeted ES cells were injected into C57BL/6 blastocysts. The resulting chimeric males were bred to C57BL/6NCr females, and offspring were bred to B6.C-Tg(CMV-cre)1Cgn/J mice (Stock No. 006054) to remove the floxed neo cassette. Progeny were crossed to remove the cre transgene, and resulting mice were bred to C57BL/6NCr for at least 10 generations. Upon arrival at The Jackson Laboratory, mutant mice were bred to C57BL/6NJ (Stock No. 005304) mice for at least one generation to establish the colony.
|Allele Name||targeted mutation 1.1, Edward I Ginns|
|Allele Type||Targeted (Hypomorph)|
|Allele Synonym(s)||Gbatm1.1Abmb; L444P|
|Gene Symbol and Name||Gba, glucosidase, beta, acid|
|Strain of Origin||129X1/SvJ|
|Molecular Note||A point mutation resulted in L444P substitution was introduced by PCR mutagenesis. Cre mediated recombination removed loxP-flanked neomycin cassette between metaxin and glucocerebrosidase, leaving only a 34 bp loxP sequence. Gba activity decreased to approximately 35% of the enzyme activity in normal mice.|
When maintaining a live colony, homozygous mice may be bred together.
When using the Gba*L444P mouse strain in a publication, please cite the originating article(s) and include JAX stock #024574 in your Materials and Methods section.