These floxed mutant mice possess loxP sites flanking exon 2 of the Ptchd1 gene. This strain may be useful for generating conditional mutations in studies of GABAergic neurons in the thalamic reticular nucleus and attention deficit and hyperactivity.
Guoping Feng, Massachusetts Institute of Technology
The X linked Ptchd1 gene is predicted to encode a twelve-pass transmembrane protein receptor with a sterol-sensing domain5, prompting its classification as a member of the Patched family and speculation that it may function as a Sonic hedgehog receptor and is expressed in GABAergic neurons of the thalamic reticular nucleus. Mutations in this gene have been associated with attention-deficit hyperactivity disorder and intellectual disability.
These mice possess loxP sites on either side of exon 2 of the targeted 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 2 deleted in the cre-expressing tissues.
Removal of the floxed sequence creates a null allele (expression has been assessed in brain only).
When bred to a strain with Cre recombinase expression in somatostatin-expressing neurons (see Stock No. 028864 for example), this mutant mouse strain may be useful in studies of attention deficit and hyperactivity.
A targeting vector containing a FRT-site flanked NEO selection cassette was used to insert loxP sites flanking exon 2. This selection cassette was inserted downstream of exon 2 of the targeted gene, and another loxP site was inserted upstream of exon 2. This construct was electroporated into (129X1/SvJ x 129S1/Sv)F1- Kitl+-derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts.
The resulting chimeric male animals were backcrossed to wildtype C57BL/6J female mice. The mice were then crossed to C57BL/6J β-actin Flp mice to remove the NEO cassette, and then crossed to C57BL/6J for 5 generations, using a marker assisted protocol.
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 Name||targeted mutation 2.1, Guoping Feng|
|Allele Type||Targeted (Conditional ready (e.g. floxed))|
|Allele Synonym(s)||Ptchd1 fl|
|Gene Symbol and Name||Ptchd1, patched domain containing 1|
|Strain of Origin||(129X1/SvJ x 129S1/Sv)F1-Kitl+|
|Molecular Note||A targeting vector containing a FRT-site flanked NEO selection cassette was used to insert loxP sites flanking exon 2. This selection cassette was inserted downstream of exon 2 of the targeted gene, and another loxP site was inserted upstream of exon 2. Flp-mediated recombination removed the selection cassette.|
When maintaining a live colony, these mice can be bred as homozygous females and hemizygous males (the gene is X linked).
When using the floxed Ptchd1 mouse strain in a publication, please cite the originating article(s) and include JAX stock #029343 in your Materials and Methods section.