NOD.Cg-Ins2^tm1Mnt Ins1^tm1Jja/J

Stock number: 033910
Product name: Ins2^l Ins1^-

Research areas: Diabetes and Obesity Research, Research Tools

Description

Ins2^l Ins1^- mice carry an Ins1 KO allele and the conditional Ins2^tm1Mnt allele. When combined with a cre-expressing strain, offspring will be insulin-deficient in cre-expressing tissues and may be useful for studying diabetes.

Detailed description

Ins1 (insulin 1) on chromosome 19 and Ins2 (insulin 2) on chromosome 2 encode the two insulin genes in the mouse. Insulin is a peptide hormone involved in the regulation of carbohydrate and lipid metabolism. Ins2^l is a conditional allele with loxP sites flanking exons 1-3, Ins1^- is a knockout (KO) allele with neomycin replacing most of the coding sequence, the alleles have been introgressed onto the diabetes susceptible NOD/ShiLtJ background. Mice that are heterozygous for the KO allele and the floxed allele are viable and fertile.  THe donating investigator has not generated homozygous mice. When combined with a cre-expressing strain, offspring will be insulin-deficient in cre-expressing tissues and may be useful for studying diabetes.

Of note, NOD.Cg-Ins2^tm1Mnt/J (Stock No. 034381) also is available.

Development

The Ins1^- targeting construct uses a neomycin cassette to replace most of the Ins1 coding sequences. The construct was electroporated into D3 (129S2/SvPas derived) embryonic stem cells (ES cells). Correctly targeted ES cells were injected into blastocysts. The resulting chimeric males were mated to C57BL/6 and subsequently intercrossed to generate homozygotes. Dr. George Eisenbarth's laboratory received B6.129S2-Ins1^tm1Jja from Dr. Jacques Jami and backcrossed this mutation to NOD for 11 generations. In 2004, N11 mice were received at The Jackson Laboratory, backcrossed to NOD/LtJ once, and then maintained homozygote x homozygote. Mice from this colony were used to generate the double mutant.

The Ins2^l targeting construct contains a loxP site inserted upstream of exon1 and an FRT-flanked neomycin cassette inserted downstream of exon 3 followed by a loxP-site. The construct was electroporated into unspecified embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric males were crossed to 129S4/SvJaeSor-Gt(ROSA)26Sor^tm1(FLP1)Dym/J (Stock No. 003946) females to remove the neomycin cassette. Offspring were interbred to produce a homozygous colony and the FLP transgene was bred out.

Dr. James Johnson of the University of British Columbia combined the Ins2^tm1Jja and Ins2^tm1Mnt and the Gt(ROSA)26Sor^{tm4(ACTB-tdTomato,-EGFP)Luo} alleles on the NOD/ShiLtJ background using a marker-assisted speed congenic approach.The Gt(ROSA)26Sor^{tm4(ACTB-tdTomato,-EGFP)Luo} has been bred out of this strain.

Allele

Symbol: Ins2^tm1Mnt
Name: targeted mutation 1, Massimo Trucco
MGI accession ID: MGI:4361633
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Synonyms: Ins2^l
Marker symbol: Ins2
Marker name: insulin II
Marker synonyms: CP-II; IDDM; IDDM1; IDDM2; ILPR; Ins-2; InsII; IRDN; Mody; MODY10; Mody4; PNDM4
Chromosome: 7
Strain of origin: Not Specified
Molecular note: The targeting construct contains loxP sites flanking the mouse Ins2 gene. An Frt-flanked Neo cassette was inserted after the Ins2 exon 3 before the loxP site. The construct was injected into ES cells to modify the endogenous locus through homologous recombination. Mice expressing this allele were generated and subsequently crossed to 129S4/SvJaeSor-Gt(ROSA)26Sor^tm1(FLP)Dym/J mice to delete the Neo cassette.

Allele

Symbol: Ins1^tm1Jja
Name: targeted mutation 1, Jacques Jami
MGI accession ID: MGI:2181877
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: Ins1^-
Marker symbol: Ins1
Marker name: insulin I
Marker synonyms: IDDM; IDDM1; IDDM2; ILPR; IRDN; MODY10; PNDM4
Chromosome: 19
Strain of origin: 129S2/SvPas
Molecular note: The majority of the coding region was replaced with a neomycin selection cassette. RT-PCR analysis showed an absence of transcript in homozygous mutant mice.