Male mice lacking expression of corticotropin releasing hormone receptor 2 (Crhr2) exhibit enhanced anxious behavior in several tests of anxiety. Female targeted mutant mice do not show this increase of anxiety-like behavior.
Michael Geoff Rosenfeld, University of California, San Diego
Male mice lacking expression of corticotropin releasing hormone receptor 2 (Crhr2) exhibit enhanced anxious behavior in several tests of anxiety, including the elevated plus-maze test and the dark-light emergence task. Female targeted mutant mice do not show this increase of anxiety-like behavior. Mice show impaired responses in specific brain regions involved in emotional and autonomic function as monitored by a reduction of Creb phosphorylation in male, but not female, homozygous targeted mice. Male and female deficient animals display a larger edema response in response to thermal injury than do their wild-type littermates.
Three exons encoding a cytoplasmic region (third intracellular loop) of the targeted gene were replaced with a neomycin resistance cassette. The (129X1/SvJ x 129S1/Sv)F1- Kitl+-derived R1 embryonic stem (ES) cell line was used to create the mutation. Repeated backcrosses to C57BL/6 were found to contribute to a reduced recovery of homozygotes. The strain was backcrossed 8-10 times to C57BL/6 by the donating laboratory. A SNP (single nucleotide polymorphism) panel analysis performed by The Jackson Laboratory revealed that this strain was on a mixed background involving C57BL/6 upon importation.
|Allele Name||targeted mutation 1, Joachim Speiss|
|Allele Type||Targeted (Null/Knockout)|
|Gene Symbol and Name||Crhr2, corticotropin releasing hormone receptor 2|
|Strain of Origin||(129X1/SvJ x 129S1/Sv)F1-Kitl+|
|Molecular Note||A neomycin selection cassette replaced a genomic fragment containing exons which encode the third intracelllular loop. Binding assays on sections of adult homozygous brain confirmed that no functional protein was expressed from this allele. No detectable transcript was produced from this allele (data not shown).|
|Mutations Made By|| |
Joachim Spiess, Salk Institute
When maintained as a live colony, homozygotes or heterozygotes may be bred. Repeated backcrosses to C57BL/6 may contribute to a reduced recovery of homozygotes.
When using the Crhr2- mouse strain in a publication, please cite the originating article(s) and include JAX stock #010842 in your Materials and Methods section.