B6.Cg-Crb1^rd8 Prkcq^tm1Litt/JBoc

Stock number: 031293
Research areas: Cell Biology Research, Developmental Biology Research, Immunology, Inflammation and Autoimmunity Research, Mouse/Human Gene Homologs, Sensorineural Research

Description

This knockout allele causes severely impaired T helper cell (Th2) immune responses, retinal detachment, as well as abnormal insulin signaling and glucose transport. These mice are suitable for use in applications related to T cell development, Th2-mediated disease, asthma, diabetes, and exudative retinal detachment.

Detailed description

Mice homozygous for the Prkcq^tm1Litt targeted allele are viable, fertile, normal in size, and do not display any behavioral abnormalities. No endogenous or truncated protein product was detected in thymocytes or T cells. Mature T lymphocytes from null mice have blunted proliferative responses with decreased levels of both IL-2 and IL-2 receptor, and defective T cell receptor-initiated IkappaB-degradation/NF-kappaB activation. Homozygous mice exhibit severely impaired Th2, but normal Th1, immune responses as well as abnormal insulin signaling and glucose transport. Mutant mice also have defective regulatory T cell development (very low CD25 expression). Additionally, homozygotes develop retinal detachments and late-onset retinal pigment epithelium atrophy. This strain is also homozygous for the Crb1^rd8 mutation, which itself causes retinal spotting and retinal degeneration. Crb1^rd8 is also absent from Stock No. 028488. This mutant may be suitable for use in studies related to T cell proliferation/signal transduction/immunodeficiency, Th2-mediated disease, asthma, diabetes, and exudative retinal detachment. No significant difference in ocular phenotype has been detected between mice homozygous for Prkcq^tm1Litt and wild-type at Crb1 with those doubly homozygous for both Prkcq^tm1Litt and Crb1^rd8.

Development

A targeting vector replaced the endogenous exon coding for the ATP-binding site of the kinase domain (amino acids 396-451) of Prkcq with the neomycin resistance gene. The construct was electroporated into the 129P2/OlaHsd-derived E14 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts. The resulting chimeric mice were bred to C57BL/6. Heterozygotes were backcrossed to an undefined C57BL/6 subline for 15 generations before being made homozygous. These mice were imported into The Jackson Laboratory from Dr. Dan Littman and embryos were cryopreserved from homozygous males bred to C57BL/6J females, see stock #005711. An ocular screen of cryo-recovered mice by Dr. Bo Chang identified the retinal detachments and late-onset retinal pigment epithelium atrophy, attributable to Prkcq mutations. It was also discovered that the Crb1^rd8 mutation, which is homozygous in C57BL/6N and C57BL/6By sublines but absent from C57BL/6J, was segregating in the cryo-recovered mice. These mice were again backcrossed to C57BL/6J, intercrossed and selected for the presence or absence of Crb1^rd8 along with the presence of Prkdc^tm1Litt, yielding this strain, homozygous for both Crb1^rd8 and Prkdc^tm1Litt and stock #028488, B6.Cg-Crb1⁺ Prkcq^tm1Litt/Boc.

Allele

Symbol: Crb1^rd8
Name: retinal degeneration 8
MGI accession ID: MGI:2676366
Generation method: Spontaneous
Synonyms: Crb1^6N; nmf144; Rd8^-
Marker symbol: Crb1
Marker name: crumbs family member 1, photoreceptor morphogenesis associated
Marker synonyms: 7530426H14Rik; A930008G09Rik; CRB1-A; CRB1-B; CRB1-C; LCA8; RP12
Chromosome: 1
Strain of origin: C57BL/6By or C57BL/6N
Molecular note: The mutation in the rd8 mouse has been identified as a single base deletion of a C (G on forward strand) at coding nucleotide 3481 in the gene. This deletion causes a frame shift and a premature stop codon that truncates the transmembrane and cytoplasmic domain of the protein after amino acid 1207. This mutation has been found to be present in all sublines of C57BL/6N and in C57BL/6ByJ, but not in any C57BL/6J subline. It occurred sometime between transfer of mice from JAX to NIH, in 1951, and from NIH to Donald Bailey, in 1961.

Allele

Symbol: Prkcq^tm1Litt
Name: targeted mutation 1, Dan Littman
MGI accession ID: MGI:2664379
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: PKC-Theta^-; PKCtheta^-
Marker symbol: Prkcq
Marker name: protein kinase C, theta
Marker synonyms: A130035A12Rik; nPKC-theta; PKC theta; PKC-0; Pkcq; PKCtheta; PKC-theta; PRKCT
Chromosome: 2
Strain of origin: 129P2/OlaHsd
Molecular note: The exon encoding the ATP-binding site of the kinase domain (aa 396 - 451) was replaced with a neo cassette inserted by homologous recombination. Protein was undetected in thymocytes or T cells obtained from mutant mice.