B6;FVB-Ifi208^{Tg(Cspg4-cre)1Akik}/J

Stock number: 008533
Research areas: Neurobiology Research, Research Tools

Description

These transgenic mice express the Cre recombinase under the control of the mouse chondroitin sulfate proteoglycan 4 (Cspg4) promoter/enhancer. Cre recombinase expression is detected in Cspg4 expressing glial cells and vasculature throughout the brain as well as in Cspg4-expressing cells in other tissues from late embryonic stages (~embryonic day 14) throughout adulthood. These transgenic mice may be may be crossed to various floxed mutants to delete floxed sequences specifically in Cspg4-expressing cells.

Detailed description

These transgenic mice express Cre recombinase under the control of the mouse chondroitin sulfate proteoglycan 4 (Cspg4) promoter/enhancer. The transgene integrated into an intron of Ifi208 (interferon activated gene 208) of chromosome 1. Founder line 1 has a copy number of 1-3. Mice hemizygous for the NG2creBAC transgene are viable and fertile, normal in size and do not display any gross physical or behavioral abnormalities. Cre recombinase expression is detected in NG2 expressing glial cells and vasculature throughout the brain as well as in NG2-expressing cells in other tissues from late embryonic stages (~embryonic day 14) throughout adulthood. The efficiency of Cre-mediated recombination is less than 100% (86% in forebrain and 70-75% in spinal cord). Immunoreactive Cre was not detected in S100beta+ or GFAP+ astrocytes or APC+ oligodendrocytes. These NG2creBAC transgenic mice may be may be crossed to various floxed mutants to delete floxed sequences specifically in NG2-expressing cells. The donating investigator reports that there appears to be transient Cre expression in some projection neurons and interneurons scattered throughout the cerebral cortex, hippocampus, spinal cord, and other regions after postnatal day 30 and in male germ cells.

Additional Note: This strain needs to be monitored by quantitative PCR specific for cre. Breeding through the male germline leads to copy number loss and poor expression. It is maintained by breeding carrier females with noncarrier or C57BL/6J males only.

Development

A 208 kb RPCI-23 C57BL/6J mouse bacterial artificial chromosome (BAC) containing the entire NG2 (Cspg4) gene (and 60 kbp of 5' and 114 kbp of 3' flanking sequences) was modified by inserting a cre recombinase coding sequence with a nuclear localization signal followed by a rabbit beta-globin polyA signal into the first exon of the NG2 gene. The NG2 translation initiation ATG was changed to AAG to prevent translation from the BAC NG2 gene and to allow translation from the first ATG in the Cre recombinase sequence. DNA from a correctly modified BAC clone was used as the source for the NG2creBAC transgene was microinjected into the pronucleus of fertilized oocytes from C57BL/6J mice. Founder mice were subsequently established. The transgene integrated into an intron of Ifi208 (interferon activated gene 208) of chromosome 1. Founder line 1 has a copy number of 1-3. The transgenic mice were maintained on a mixed C57BL/6 and FVB genetic background prior to arrival at The Jackson Laboratory.

Allele

Symbol: Ifi208^{Tg(Cspg4-cre)1Akik}
Name: transgene insertion 1, Akiko Nishiyama
MGI accession ID: MGI:3778062
Generation method: Transgenic
Attributes: Recombinase-expressing
Marker symbol: Ifi208
Marker name: interferon activated gene 208
Chromosome: 1
Strain of origin: (C57BL/6 x SJL)F1
Expressed genes: cre,cre recombinase,bacteriophage P1
Site of expression: NG2 expressing glial cells and vasculature throughout the brain as well as in NG2-expressing cells in other tissues from late embryonic stages (~embryonic day 14) throughout adulthood
Molecular note: The transgene construct consisted of the 208 kb C57BL/6J mouse bacterial artificial chromosome (BAC) RP23-309G21, containing the entire NG2 (Cspg4) gene (and 60 kbp of 5' and 114 kbp of 3' flanking sequences), which was modified by inserting an nls-cre coding sequence followed by a rabbit beta-globin polyA signal into the first exon of the NG2 gene. The NG2 translation initiation ATG was changed to AAG to prevent translation from the BAC NG2 gene and to allow translation from the first ATG in the cre sequence. Cre expression is detected only in Cspg4-expressing cells at P1, P14 and P60 and not in Gfap +ve astrocytes or APC +ve oligodendrocytes. Activity is also detected in male germ cells. Line 1 inserted into an intron of the gene at 173692115 (Build GRCm38/mm10). Founder line 1 has a copy number of 1-3.