These floxed mutant mice possess loxP sites flanking exon 9 of the Ep300 gene. This strain may be useful for generating conditional mutations in applications related to T-cell development and hematopoiesis.
Paul K. Brindle, St. Jude Children's Research Hospital
The Ep300 gene encodes the E1A binding protein p300 and the Crebbp gene encodes the CREB binding protein, both of which are highly conserved coactivators that promote transcription and are important to the function of many hematopoietic transcription factors.
These mice possess loxP sites on either side of exon 9 of the Ep300 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 exon 9 deleted in the cre-expressing tissues.
When bred to a strain with Cre recombinase expression in thymocytes (for example, see Stock No. 003802 for example), this mutant mouse strain may be useful in studies of T-cell development.
A loxP and FRT site flanked NEO/chloramphenicol selection cassette was utilized in the construction of this mutant. This selection cassette was inserted into the 3’ intron of exon 9 of the targeted gene, and another loxP site was inserted into the 5’ intron of exon 9, with the Tn7 transposon-based system. This construct was electroporated into 129P2/OlaHsd derived E14 embryonic stem (ES) cells which were transiently transfected with a Flp recombinase expression plasmid. Correctly targeted ES cells that had successfully undergone FLP recombination and no longer retained the selection cassette but did retain the loxP-flanked exon 9 were injected into blastocysts. The resulting chimeric animals were tested for germline transmission. The mice were backcrossed to C57BL/6J for 18 generations, with female heterozygotes backcrossed to a wildtype C57BL/6J male at N3, N8, and N16. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) at least once to establish the colony.
|Allele Name||targeted mutation 2, Paul K Brindle|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Ep300, E1A binding protein p300|
|Strain of Origin||129P2/OlaHsd|
|Molecular Note||Exon 9 is flanked by LoxP sites (in same orientation). There also is one Frt site 3' of exon 9 left from removal of selection cassette. Absence of transcription and translation products was confirmed by QRT-PCR, immunohistochemistry, and Western blot analysis.|
When maintaining a live colony, these mice can be bred as homozygotes.
When using the p300flox mouse strain in a publication, please cite the originating article(s) and include JAX stock #025168 in your Materials and Methods section.