Exons 9-11 of Gba (glucosidase, beta, acid) are flanked by loxP sites in this conditional model, useful in studies of Gaucher disease.
Lorne A Clarke, University of British Columbia
Inherited deficiency of the lysosomal hydrolase, glucocerebrosidase (encoded by Gba, glucosidase, beta, acid) underlies the autosomal recessive disorder, Gaucher disease. Excessive glucocerebroside storage may lead to the associated tissue dysfunctions. Affected individuals present with a spectrum of clinical symptoms ranging from hepatosplenomegaly, haematological abnormalities, and bone pain, to severe neurodegeneration and premature death. Homozygous knockouts of Gba in mice are perinatal lethal.
In this targeted allele, exons 9-11 are flanked by loxP sites enabling tissue-directed knockouts of the locus via Cre excision. Incomplete expression of Tie2Cre-recombinase (see Stock No. 004128) in cells of hematopoietic and endothelial origin results in deficiency of glucocerebrosidase in the liver, spleen, bone marrow, and peripheral white cells. Glucocerebroside storage in this model leads to progressive splenomegaly with Gaucher cell infiltration and modest storage in the liver by 26 weeks of age. No animals displayed obvious pathology in the bone marrow by 26 weeks of age, but small numbers of Gaucher cells could be found. No obvious haematological differences were seen in affected animals at 26 weeks of age.
A targeting vector was designed to place loxP sites on either side of Gba exons 9-11 and place an FRT-flanked neomycin cassette in reverse transcriptional orientation in intron 11. The targeting vector was injected into (129X1/SvJ x 129S1/Sv)F1- Kitl+-derived R1 embryonic stem (ES) cells. A Flpe-recombinase expression plasmid was introduced to targeted ES cells by electroporation to remove the neomycin resistance cassette. This strain was backcrossed to C57BL/6J for 11 generations by the donating laboratory.
|Allele Name||targeted mutation 1, Lorne A Clarke|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Gba, glucosidase, beta, acid|
|Strain of Origin||(129X1/SvJ x 129S1/Sv)F1-Kitl+|
|Molecular Note||A targeting vector was designed to flank exons 9-11 with loxP sites. An frt-flanked neo was inserted as well as exons 8-4 of metaxin 1 in reverse orientation. The neo was removed by transient expression of FLP recombinase.|
Homozygous and heterozygous floxed mice are viable and fertile.
When using the FloxGBA mouse strain in a publication, please cite the originating article(s) and include JAX stock #021329 in your Materials and Methods section.