C57BL/6-Pabpn1^tm2.1Gpvl/J

Stock number: 029237
Product name: Pabpn1 floxed
Research areas: Neurobiology Research, Research Tools

Description

Pabpn1 floxed mice possess a loxP sited flanking exons 1-2, including the start codon, of the poly(A) binding protein, nuclear 1 (Pabpn1) gene. These mice may be useful when studying Oculopharyngeal muscular dystrophy (OPMD).

Detailed description

Pabpn1 floxed mice possess loxP sites flanking exons 1-2 of the poly(A) binding protein, nuclear 1 (PABPN1) gene. PABPN1 is a ubiquitously expressed RNA binding protein that is most well characterized as a regulator of polyadenosine (poly[A]) tail length and alternative polyadenylation (APA), as well as a regulator of expression of antisense RNAs associated with gene promoters. A stretch of ten alanines just after the initial methionine and a dominant GCG expansion to 11-18 alanines in PABPN1 is associated with the onset of Oculopharyngeal muscular dystrophy (OPMD). This is a late onset disease that causes ptosis, dysphagia, and loss of mobility due to progressive weakness of eyelid, pharyngeal, and proximal limb muscles. Patients are affected by loss of nutrition and aspiration pneumonia. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exons 1-2, including the start codon and the 10-alanine residues, removed in cre-expressing tissues. Mice that are homozygous for this allele are viable and fertile.

When bred to B6.FVB-Tg(EIIa-cre)C5379Lmgd/J (Stock No. 003724) mice, with early embryonic Cre Recombinase expression, resulting Pabpn1 deficient mice exhibit mild myopathic phenotype in adult and aged animals. They have shorter poly(A) tails and evidence of mitochondrial damage as noted by loss of mtDNA copy number. They also have smaller hind limb muscles.

Development

The Pabpn1 floxed targeting vector was designed to insert a loxP-site upstream of the start codon of the poly(A) binding protein, nuclear 1 (Pabpn1) gene, and a frt-flanked puromycin resistance (puro) cassette and a second loxP-site downstream of exon 2. The construct was electroporated into C57BL/6-derived HZ1.1 embryonic stem (ES) cells. Correctly targeted ES cells were transiently transfected with a FLP expression plasmid to delete the puro cassette. Resulting ES cells were injected into blastocysts and chimeric males were bred with C57BL/6J females, and were subsequently bred to C57BL/6J mice for at least 5 generations. 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: Pabpn1^tm2.1Gpvl
Name: targeted mutation 2.1, Grace Pavlath
MGI accession ID: MGI:5888724
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed)
Marker symbol: Pabpn1
Marker name: poly(A) binding protein, nuclear 1
Chromosome: 14
Strain of origin: C57BL/6
Molecular note: A loxP site was inserted upstream of exon 1 and an FRT site flanked puromycin resistance gene cassette and a second loxP site into intron 2. The puro cassette was removed through subsequent Flp-mediated recombination. Exons 1 and 2 were deleted through Cre-mediated recombination, creating a null allele.
General note: ES cell line = HZ1.1