C57BL/6-Khdrbs1^tm1Gqin/J

Stock number: 037100
Product name: Sam68^f
Research areas: Cell Biology Research, Diabetes and Obesity Research, Research Tools

Description

Sam68^f/f floxed mice have loxP sites flanking exons 5-8 of the Khdrbs1 gene. This mutant mouse strain may be useful in studies of hepatic gluconeogenesis and type 2 diabetes.

Detailed description

Sam68^f/f floxed mice have loxP sites flanking exons 5-8 of the KH domain containing, RNA binding, signal transduction associated 1 (Khdrbs1) gene. Khdrbs1, also known as Sam68, encodes an RNA-binding adaptor protein and Src kinase substrate involved in numerous cellular functions, including RNA processing, kinase- and growth-factor-signaling, transcription, cell-cycle regulation, and apoptosis. It is also a novel regulator of hepatic gluconeogenesis, which is crutial for glucose homeostasis. Hepatic SAM68 expression has been shown to be upregulated in diabetic mouse models, while hepatocyte-specific SAM68 deficiencies alleviate diabetic hyperglycemia and improves insulin sensitivity. SAM68 also affects alternative splicing of a number of genes involved in neurogenesis and adipogenesis as well as diseases such as spinal muscular atrophy (SMA) and cancer.

Mice that are homozygous for this allele are viable and fertile. The presence of an intact neomycin resistance cassette has been shown to have no effect on the normal expression of SAM68 in these mice. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have exons 5-8 removed in the Cre-expressing tissues of the offspring.

When bred to Alb-cre mice (see Stock No. 003574), expressing cre recombinase in the liver, resulting Sam68^LKO mice have exons 5-8 deleted. Sam68^LKO mice have significantly reduced blood glucose levels and reduced glucagon-induced expression of gluconeogenic genes. Protein, but not mRNA, levels of CRTC2, a crucial transcriptional regulator of gluconeogenesis, are >50% lower in Sam68^LKO hepatocytes than in wild-type hepatocytes.

Development

The Sam68^f targeting vector was designed to insert a loxP site upstream of exon 5 of the KH domain containing, RNA binding, signal transduction associated 1 (Khdrbs1) gene. A neomycin resistance cassette, followed by a second loxP site, was inserted downstream of exon 8. The construct was electroporated into C57BL/6N-derived embryonic stem (ES) cells and correctly targeted ES cells were injected into blastocysts. Resulting chimeric mice were bred with C57BL/6J mice (Stock No. 000664) for at least six generations before being intercrossed to produce homozygous Sam68^f/f mice. Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes.

Allele

Symbol: Khdrbs1^tm1Gqin
Name: targeted mutation 1, Gangjian Qin
MGI accession ID: MGI:7266287
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed)
Marker symbol: Khdrbs1
Marker name: KH domain containing, RNA binding, signal transduction associated 1
Chromosome: 4
Strain of origin: C57BL/6N
Molecular note: The targeting vector is designed to insert a loxP site upstream of exon 5. A neomycin resistance cassette, followed by a second loxP site, was inserted downstream of exon 8.