STOCK Asxl1^tm1.1Iaai/J

Stock number: 025665
Product name: Asxl1^fl
Research areas: Cancer Research, Research Tools

Description

These floxed mutant mice possess loxP sites flanking exons 5 through 10 of the Asxl1 gene. This strain may be useful for generating conditional mutations in applications related to embryonic development, myelodysplastic syndromes and hematopoiesis.

Detailed description

These mice possess loxP sites flanking exons 5 through 10 of the targeted Asxl1 gene. Mice that are homozygous for this allele are viable and fertile. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exons 5 through 10 deleted in the cre-expressing tissues. During backcrossing, the Y chromosome may not have been fixed to the C57BL/6J genetic background.

When bred to the EIIa-cre strain with germline Cre recombinase expression in the germline (see Stock No. 003724 for example), this mutant mouse strain may be useful in studies of skeletal and craniofacial abnormalities such as microphthalmia and anophthalmia.

When bred to a strain with Cre recombinase expression in the hematopoietic system (see Stock No. 003556 for example), this mutant mouse strain may be useful in studies of myelodysplastic syndromes.

Development

A FRT and loxP site flanked targeting vector containing PGK-Neo selection cassette was utilized in the construction of this mutant. This selection cassette was inserted downstream of exon 5 of the targeted gene, and another loxP site was inserted upstream of exon 10. This construct was electroporated into C57BL/6 x 129S/SvEv derived BAC-BA1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric animals were crossed to germline Flp deleter mice, on the C57BL/6 genetic background, expressing FLP recombinase. to remove the selection cassette. Mice that retained the loxP site flanked exons 5 through 10 were then bred to C57BL/6 mice for 7 generations by the donating lab (see SNP note below). During backcrossing, the Y chromosome may not have been fixed to the C57BL/6J genetic background. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) 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. Two of the 27 markers throughout the genome were still segregating, suggesting an incomplete backcross. Also, 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: Asxl1^tm1.1Iaai
Name: targeted mutation 1.1, Iannis Aifantis
MGI accession ID: MGI:5575656
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Marker symbol: Asxl1
Marker name: additional sex combs like 1
Chromosome: 2
Strain of origin: (C57BL/6 x 129S/SvEv)F1
Molecular note: Two loxP sites flanking exon 5-10 and an Frt-flanked neomycin selection cassette were inserted in the upstream intron. Flp-mediated recombination removed the neomycin cassette and left exons 5-10 floxed.