B6.Cg-Dbh^{tm3.2(cre)Pjen}/J

Stock number: 033951
Product name: Dbh^cre KI/KO
Research areas: Developmental Biology Research, Research Tools

Description

Dbh^cre knock-in/knock-out mice express Cre recombinase from the endogenous Dbh locus, abolishing endogenous Dbh gene expression. Cre recombinase activity is detected in noradrenergic neurons.

Detailed description

These Dbh^cre knock-in mice express Cre recombinase from the endogenous Dbh (dopamine beta hydroxylase) locus, directing Cre recombinase activity in noradrenergic and adrenergic neurons. Insertion of Cre abolishes Dbh gene expression. The targeted Dbh gene encodes an oxidoreductase that catalyzes the oxidative hydroxylation of dopamine to norepinephrine. Mutations in this gene have been associated with Orthostatic Hypotension 1. Mice that are heterozygous for the targeted mutation are viable and fertile. Homozygotes are not viable (embryonic lethal) due to loss of norepinephrine synthesis.

Development

A targeting vector was utilized to insert a rox-flanked transcriptional STOP cassette, Cre recombinase cDNA, a rabbit beta-globin polyadenylation cassette, and an attB/attP-flanked neomycin resistance cassette directly after the start codon of Dbh. The construct was electroporated into (129S6/SvEvTac x C57BL/6NCrl)F1 derived G4 embryonic stem (ES) cells which were transiently transfected with the PhiC31 recombinase plasmid, pPGKPhiC31obpa, to remove the selection cassette. ES cells that had successfully undergone PhiC31-mediated recombination and no longer retained the selection cassette were injected into B6(Cg)-Tyr^c-2J/J blastocysts. The resulting chimeric animals were tested for germline transmission. The mice were then bred to B6;129-Tg(CAG-dre)1Afst to excise the rox-flanked STOP cassette, thus generating the Dbh^cre knock-in mice. The Dre recombinase transgene was removed from the mice by breeding to C57BL/6J for 17 generations. Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6NJ oocytes (Stock No. 000664).

Allele

Symbol: Dbh^{tm3.2(cre)Pjen}
Name: targeted mutation 3.2, Patricia Jensen
MGI accession ID: MGI:6305870
Generation method: Targeted
Attributes: Recombinase-expressing
Synonyms: Dbh^cre
Marker symbol: Dbh
Marker name: dopamine beta hydroxylase
Marker synonyms: DBM; DOPBHY; ORTHYP1
Chromosome: 2
Strain of origin: (129S6/SvEvTac x C57BL/6NCrl)F1
Site of expression: Noradrenergic neurons.
Molecular note: A rox-flanked transcriptional stop cassette, cre cDNA, rabbit beta-globin polyadenylation cassette, and attB/attP-flanked neomycin resistance cassette were inserted into the Dbh locus, immediately following the start codon by homologous recombination. A recombinant clone was transiently transfected with pPGKPhiC31obpa to excise the neomycin resistance cassette before cells were injected into blastocysts to produce chimeric mice. Following germline transmission, heterozygotes were crossed with Dre expressing mice to remove the rox-flanked stop cassette.