129S.129P2(B6)-Crebbp^tm2Pkb/J

Stock number: 025531

Description

Portions of the CH1 domain were deleted from the Crebbp gene to create these hypomorphic p300 deltaCH1 mice that are useful in studies of hypoxia-responsive transcription.

Detailed description

Crebbp (CREB binding protein, also known as CBP) is a protein acetyltransferase that is required for normal development. It interacts with a significant percentage of mammalian transcriptional regulatory proteins and has a CH1 domain that binds the C-terminal activation domain (C-TAD) of the hypoxia-inducible transcription factors HIF-1α and HIF-2α. This interaction is highly essential for hypoxia-responsive transcription, and is relevant to processes of glucose metabolism, angiogenesis, hematopoiesis, cell survival, invasion, and vascular tone.

These mice carry a targeted, partial, in-frame deletion of the CH1 domain in the mouse Crebbp gene (amino acids 342-393) that results in a hypomorphic protein. Western blots indicate that normal levels of a stable protein with intact HAT domain are produced. Heterozygotes on a mixed C57BL/6-129 mixed background are produced at reduced frequency and homozygotes typically die shortly after birth. C57BL/6-129 mixed background embryos examined at embryonic day 18.5 (E18.5) exhibit lung defects. Homozygous F1 hybrids generated by crossing this 129 backcrossed line (Stock No. 025531) with the same mutation on a C57BL/6-backcrossed background (see Stock No. 025172) show markedly enhanced survival to adulthood (~25% of the expected frequency), but are growth retarded and have craniofacial defects.

Development

Portions of the CH1 domain (amino acids 342-393) was deleted and a neomycin resistance cassette flanked by FRT sites was introduced to the upstream intron through homologous recombination in 129P2/OlaHsd-derived E14.1 embryonic stem (ES) cells. Transient infection of the ES cells with a Flp-expressing vector excised the neomycin cassette. Resultant chimeric mice were crossed with C57BL/6J animals, then to 129P2/Ola for 2 generations. Fertility/productivity issues precipitated 27 generations of backcrossing to 129S2/SvPasCrl by the donating laboratory.

Allele

Symbol: Crebbp^tm2Pkb
Name: targeted mutation 2, Paul K Brindle
MGI accession ID: MGI:3612048
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Crebbp
Marker name: CREB binding protein
Chromosome: 16
Strain of origin: 129P2/OlaHsd
Molecular note: Portions of the CH1 domain (amino acids 342-393) was deleted and a neomycin resistance cassette flanked by loxp sites was introduced to the upstream intron. Transient infection of the ES cells with a Cre-expressing vector excised the neomycin cassette. RT-PCR confirmed the deletion in mutant MEFs.