STOCK Akap12^tm1Ihg Rb1^tm2Brn Tg(Pbsn-cre)4Prb/J

Stock number: 026229
Product name: Akap12^-/-;Rb^PE-/-
Research areas: Cancer Research, Internal/Organ Research

Description

This strain has been discontinued. Please search the JAX Mice database for other strains which may be suitable for your studies. Single strains are available as follows: Stock No. 026662 STOCK Tg(Pbsn-cre)4Prb/J; Stock No. 026563 STOCK Rb1^tm2Brn/J; Stock No. 026228 STOCK Akap12^tm1Ihg/J.

Akap12^-/-;Rb^PE-/- mice develop prostatic intraepithelial neoplasia by 2 months of age and are a model for early prostate intraepithelial neoplasia metastasis to lymph nodes.

Detailed description

These mutant mice carry a knock-out allele for Akap12 and prostate epithelium specific deletion of Rb1. In human prostate cancer, AKAP12 and RB1 are downregulated. Mice that are homozygous for the Akap12^tm1Ihg allele, homozygous for the Rb1^tm2Brn allele, and hemizygous for the Tg(Pbsn-cre)4Prb transgene, develop low grade prostatic intraepithelial neoplasia (PIN) in all prostate lobes by 2 months of age. By 5 months of age, 29% of these mice develop high-grade PIN. No adenocarcinoma is detected in mutant mice up to 24 months of age. 83% of mice exhibiting focal high-grade PIN lesions develop pelvic or inguinal lymph node metastases. Mice that are heterozygous for the Akap12^tm1Ihg allele, homozygous for the Rb1^tm2Brn allele, and hemizygous for the Tg(Pbsn-cre)4Prb transgene, are viable and fertile. 3-4% of single mutant mice homozygous for the Akap12^tm1Ihg allele die spontaneously as early as 4 months of age, and 10-25% of Akap12^tm1Ihg homozygotes are infertile or show delayed fertility (the Donating Investigator reports that breeding pairs may need to be housed for up to 3 weeks). To maintain prostate specific cre recombination, the Tg(Pbsn-cre)4Prb transgene must be inherited from the male only.

Development

These triple mutant mice were generated by crossing double mutant mice carrying the Rb1^tm2Brn allele and Tg(Pbsn-cre)4Prb transgene to mice carrying the Akap12^tm1Ihg allele.

For the Akap12^tm1Ihg allele: a targeting vector containing a lacZ-NEO cassette was used to disrupt exon 2 of the targeted gene. The construct was electroporated into 129S4/SvJae derived J1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into 129SvJ blastocysts. The resulting chimeric animals were tested for germline transmission. The mice were then backcrossed onto the C57BL/6 background for 6 generations. During backcrossing, the Y chromosome may not have been fixed to the C57BL/6 genetic background.



For the Rb1^tm2Brn allele: a targeting vector, designed by Dr. Anton Berns (The Netherlands Cancer Institute), was used to introduce loxP sites flanking exon 19 of the targeted gene. The construct was electroporated into unspecified 129 derived embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric animals were tested for germline transmission. The mice were maintained on a mixed FVB;129 background.



For the Tg(Pbsn-cre)4Prb transgene: a transgenic construct, designed by Dr.Pradip Roy-Burman (University of Southern California), containing sequence encoding Cre recombinase under the control of the rat Pbsn, probasin, gene promoter with two tandem repeats of the androgen responsive region, was injected into fertilized (C57BL/6 x DBA/2)F1 mouse eggs. Founder line 1 was subsequently established and maintained on a mixed B6;D2 background.

Allele

Symbol: Tg(Pbsn-cre)4Prb
Name: transgene insertion 4, Pradip Roy-Burman
MGI accession ID: MGI:2385927
Generation method: Transgenic
Attributes: Recombinase-expressing
Marker symbol: Tg(Pbsn-cre)4Prb
Marker name: transgene insertion 4, Pradip Roy-Burman
Chromosome: UN
Strain of origin: (C57BL/6 x DBA/2)F1
Expressed genes: cre,cre recombinase,bacteriophage P1
Site of expression: Cre recombinase is expressed in the prostate epithelium.
Molecular note: The transgene is composed of the cre recombinase gene under the control of a composite promoter derived from rat Pbsn. The rat Pbsn promoter drives postnatal transgene expression in the prostatic epithelium. The transgene is expressed postnatally in prostatic epithelium with the highest level of expression in the lateral lobe of the prostate gland. A very low level of transgene expression was detected in the seminal vesicles, testes, and ovaries. No transgene expression was detected in any of the other tissue types examined.

Allele

Symbol: Akap12^tm1Ihg
Name: targeted mutation 1, Irwin H Gelman
MGI accession ID: MGI:5286076
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Akap12
Marker name: A kinase (PRKA) anchor protein (gravin) 12
Chromosome: 10
Strain of origin: 129S4/SvJae
Molecular note: A lacZ followed by a neomycin selection cassette were inserted in exon2. Western blot analysis demonstrated the absence of all three major isoforms (alpha, beta, gamma).

Allele

Symbol: Rb1^tm2Brn
Name: targeted mutation 2, Anton Berns
MGI accession ID: MGI:1931018
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Marker symbol: Rb1
Marker name: RB transcriptional corepressor 1
Chromosome: 14
Strain of origin: 129
Molecular note: LoxP sites flanking exon 19 were introduced to the gene by homologous recombination. The targeted allele was verified by Southern blot analysis.
General note: Animals homozygous for the conditional floxed exon 19 allele did not show any tumor predisposition phenotype, and were of normal fertility.

Phenotypic Similarity to Human Syndrome: Glucagonoma J:216559 in double homozygous Rb1 and Trp53 conditional mutants.