NOD/ShiLtJ-Tg(Ins1-EGFP/GH1)14Hara/HaraJ

Stock number: 005282
Product name: NOD.MIP-GFP
Research areas: Diabetes and Obesity Research, Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

These MIP-GFP mice express a transgene containing a fusion gene joining enhanced green fluorescent protein to a fragment of the human growth hormone 1. Homozygotes develop diabetes by 9 weeks of age.

Detailed description

Donating investigator reports transgenic mice develop normally and behave similarly to controls with respect to glucose tolerence and and pancreatic insulin content. Histology confirms transgenic mice have normal islet architecture with coexpression of insulin and GFP. The enhanced GFP reporter allows the beta cells to be easily identified and purified for further studies.

Studies completed at The Jackson Laboratory indicate there is strong non-mosaic expression of green fluorescent protein in NOD/LtJ-Tg(Ins1-EGFP/GH1)14Hara/HaraJ islets. 100% of homozygous Ins1-EGFP transgenic males and females, identified by qPCR, become diabetic by 9 weeks of age. Pancreatic histopathology of homozygous mice shows beta cell loss without insulitis.
Hemizygous Ins1-EGFP mice are viable and are used for breeding. A 30-week incidence study comparing NOD/LtJ controls with mice hemizygous for the Ins1-EGFP transgene shows severely depressed diabetes incidence in these hemizygotes, with males atypically at greater risk than females. Glucose tolerance in prediabetic, Ins1-EGFP transgenic hemizygous 8-week-old males is selectively impaired compared to wild type controls. Although these 8-week-old Ins1-EGFP transgenic and wild type males did not differ in plasma insulin content; a significant decline was noted in hemizygous Ins1-EGFP transgenic males compared to normoglycemic wildtype males when sampled at 30 wk. Adoptive transfer of highly diabetogenic CTL (AI4 TCRTg Rag) CD8+ T cells produced diabetes within 8 days post-injection into NOD/Lt females, but failed to produce any diabetes or even home to islets weeks after injection into hemizygous females. Pancreatic histopathology of 31 week old, non-diabetic, hemizygous Ins1-EGFP transgenic males and females indicate peri and intra islet fibrosis, peri-insulitis and depleted beta cell granulation in 70% of the animals, while only 30% of the mice have intra islet insulitis.

This model provides a valuable tool for studying beta-cell biology, including identification of progenitor cells.

Development

This transgenic allele expresses Enhanced Green Fluorescent Protein fused to a 2.1kb fragment of human Growth Hormone under the control of Mouse Insulin Promoter 1. The transgenic construct was injected directly into NOD/LtJ oocytes. Founder 14 was mated to NOD/LtJ. In 2005, The Jackson Laboratory recieved transgenic progeny from the founder, backcrossed once to NOD/LtJ prior to brother-sister mating.

Allele

Symbol: Tg(Ins1-EGFP/GH1)14Hara
Name: transgene insertion 14, Manami Hara
MGI accession ID: MGI:3583654
Generation method: Transgenic
Attributes: Reporter
Synonyms: MIP-GFP; NOD-MIP-GFP
Marker symbol: Tg(Ins1-EGFP/GH1)14Hara
Marker name: transgene insertion 14, Manami Hara
Marker synonyms: MIP-GFP; NOD-MIP-GFP
Chromosome: UN
Strain of origin: NOD/ShiLtJ
Expressed genes: GFP,Green Fluorescent Protein,; GH1,growth hormone 1,human
Site of expression: Pancreatic islets
Molecular note: The transgene comprises a DNA fragment containing the mouse insulin 1 promoter, extending from 8.5 kb upstream of the transcription initiation site to nucleotide +12, driving expression of a fusion gene joining the 7.6-kb coding region of the enhanced green fluorescent protein (EGFP) gene to a 2.1-kb fragment of the human growth hormone 1 gene that confers high-level expression.
General note: Transgenic mice develop normally and exhibit glucose tolerance and pancreatic insulin levels similar to those of controls. Histological analysis reveals normal islet architecture and coexpression of insulin and EGFP (J:100005)