B6.129P2(Cg)-Aph1a^tm1Bdes Aph1b^tm1Bdes Aph1c^tm1Bdes/J

Stock number: 030985
Product name: conditionally targeted Aph1abc
Research areas: Neurobiology Research, Research Tools

Description

These conditionally targeted Aph1abc mutant mice possess loxP sites flanking exon 2 through exon 7 of the Aph1a gene, a knock-out allele of the Aph1b gene and loxP sites flanking exons 3 and 4 of the Aph1c gene. This strain may be useful for generating conditional mutations in applications related to neurodegeneration and Alzheimer's disease.

Detailed description

The targeted Aph1a, Aph1b, and Aph1c genes encode subunits of the gamma secretase complex which is involved in cleavage of APP (beta-amyloid precursor protein). Mutations in these genes have been associated with Alzheimer’s Disease. These Aph1A^flx, Aph1B KO, Aph1C^flx mice possess loxP sites flanking exon 2 through exon 7 of the Aph1a gene, a knock-out allele of the Aph1b gene and loxP sites flanking exons 3 and 4 of the Aph1c gene. Mice that are homozygous for these 3 alleles are viable and fertile. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exons 2 through 7 of the Aph1a gene and exons 3 and 4 of the Aph1c gene deleted in the cre-expressing tissues. Removal of the floxed sequences creates null alleles.

When bred to a strain expressing Cre recombinase in the forebrain (see Stock No. 005359 for example), this mutant mouse strain may be useful in studies of neurodegeneration.

Development

For Aph1a^tm1Bdes, Aph1A^flx: a targeting vector containing a Frt site flanked PGK-hygro selection cassette with lacZ reporter sequence was utilized in the construction of this mutant. This selection cassette and a 5’ (downstream) loxP site was inserted into intron 8 (position 3444), downstream of exon 7 of the targeted gene, and another loxP site was inserted into intron 1 (position 540), upstream of exon 2. This construct was electroporated into 129P2/OlaHsd derived E14 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6J blastocysts. The resulting chimeric male animals were crossed to C57BL/6J female mice. The mice were crossed to C57BL/6J for at least 8 generations.

For Aph1c^tm1Bdes, Aph1C^flx: a targeting vector containing a FRT-flanked PGK-hygro cassette was utilized in the construction of this mutant. This selection cassette and a 3’ (upstream) loxP site was inserted into intron 2, upstream of exon 3 of the targeted gene, and another loxP site was inserted into intron 4, downstream of exon 4. This construct was electroporated into 129P2/OlaHsd derived E14 embryonic stem (ES) cells.

For Aph1b^tm1Bdes, Aph1B KO: a targeting vector containing a modified human placental alkaline phosphatase sequence (signal peptide of CD5, a HA-tag human placental alkaline phosphatase cDNA, 3’ UTR, polyadenylation signal) and a NEO cassette was inserted into exon 1. This construct was electroporated into 129P2/OlaHsd derived E14 embryonic stem (ES) cells that already carried the Aph1c^tm1Bdes mutation. Correctly targeted ES cells were injected into C57BL/6J blastocysts. The resulting chimeric male animals were crossed to C57BL/6J female mice. The mice were crossed to C57BL/6J for at least 8 generations.

Mice carrying the Aph1a^tm1Bdes, Aph1A^flx allele, and mice carrying the Aph1b^tm1Bdes, Aph1B KO and Aph1c^tm1Bdes, Aph1C^flx alleles were intercrossed to generate these triple mutant mice. Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

Allele

Symbol: Aph1b^tm1Bdes
Name: targeted mutation 1, Bart De Strooper
MGI accession ID: MGI:3522628
Generation method: Targeted
Attributes: Reporter; Null/Knockout
Synonyms: Aph1b^-
Marker symbol: Aph1b
Marker name: aph1 homolog B, gamma secretase subunit
Marker synonyms: 2310057K14Rik; APH-1B; aph-1beta; PRO1328; PSFL; RGD1559979; TAAV688
Chromosome: 9
Strain of origin: 129P2/OlaHsd
Expressed genes: ALPP,alkaline phosphatase, placental,human
Molecular note: A targeting vector was designed to insert a modified human placental alkaline phosphatase reporter sequence, polyA signal at the ATG in exon 1. RT-PCR and Western blot of mutant MEFs demonstrated the expression of mRNA or protein, respectively.

Allele

Symbol: Aph1c^tm1Bdes
Name: targeted mutation 1, Bart De Strooper
MGI accession ID: MGI:3530441
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Synonyms: Aph1C^flx
Marker symbol: Aph1c
Marker name: aph1 homolog C, gamma secretase subunit
Marker synonyms: 0610008A10Rik; APH-1B; aph-1beta; PRO1328; PSFL; RGD1559979; TAAV688
Chromosome: 9
Strain of origin: 129P2/OlaHsd
Molecular note: A loxP site and an FRT-flanked PGK-hygro were inserted into intron 2 and a second loxP site was inserted into intron 4.

Allele

Symbol: Aph1a^tm1Bdes
Name: targeted mutation 1, Bart De Strooper
MGI accession ID: MGI:3522625
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Synonyms: Aph1A^flx
Marker symbol: Aph1a
Marker name: aph1 homolog A, gamma secretase subunit
Marker synonyms: 6530402N02Rik; APH-1; APH-1A; CGI-78; RGD1311546
Chromosome: 3
Strain of origin: 129P2/OlaHsd
Molecular note: FRT-flanked PGK-hygro with a loxP site downstream and a lacZ sequence was inserted downstream of the gene in position 3444. A second loxP site was inserted into position 540 in intron 1. RT-PCR and Western blot of mutant MEFs demonstrated the expression of mRNA or protein, respectively.