C57BL/6J-Tg(Ccr2-EGFP)8Pame/J

Stock number: 039824
Product name: CCR2.GFP
Research areas: Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

The CCR2.GFP transgenic mice express an enhanced green fluorescent protein (EGFP) under the control of the endogenous Ccr2 (C-C motif chemokine receptor 2) gene promoter and regulatory elements. These mice may be useful for studying the recruitment of monocytes to sites of inflammation and cancer from the bone marrow.

Detailed description

The CCR2.GFP transgenic mice harbor a transgene with enhanced green fluorescent protein (EGFP) sequence with a polyA sequence under the control of the endogenous Ccr2 (C-C motif chemokine receptor 2) gene promoter and regulatory elements. The CCR2 chemokine receptor is expressed on a subset of circulating monocytes including bone marrow monocytes that traffic to sites of inflammation and for bone marrow egress during infection. Bone marrow monocytes are characterized by high levels of Ly6C and in these CCR2.GFP transgenic mice, Ly6C^high monocytes are uniformly labeled with EGFP. Hemizygous and homozygous mice are viable and fertile with no overt phenotype.

Of note, in addition to these mice, the donating investigator provided The Jackson Laboratory Repository with Ccl2-RFP^lox/lox mice (Stock No. 016849), and Cc12.GFP transgenic mice (Stock No. 039821).

Development

A CCR2.GFP transgene construct was generated by bacterial artificial chromosome (BAC)-mediated transgenesis with the recombineering strategy. The endogenous Ccl2 locus was identified on BAC clone RP23-182D4 (~250 kb in size; obtained from CHORI) derived from the distal end of chromosome 9 by polymerase chain reaction (PCR) screening of candidate BACs mapped to this region. A 1.7 kb fragment that contained 1.0 kb upstream and 0.7 kb downstream of the Ccr2 gene start codon was amplified and modified between the first and second codon of the Ccr2 gene through the insertion of nucleotides that encoded aa 2-238 of enhanced GFP (EGFP). The EGFP coding sequence was followed by a stop codon, and the ensuing nucleotide at position 4 of the endogenous Ccr2 locus was deleted. The resulting 2.4 kb fragment was cloned into the shuttle vector and used to modify the BAC. The resulting modified BAC containing Gm67677, Ccr3, Gm68596, modified Ccr2 with EGFP under control of the endogenous Ccr2 promoter and regulatory elements, Ccr5, and part of Gm39469 and Gm68396 were analyzed by Southern blotting for verification of EGFP integration at the expected site; then purified and injected into fertilized C57BL/6J oocytes. Four potential founder animals were identified among 39 offspring screened by PCR and flow cytometric analysis of peripheral blood samples. One candidate, designated CCR2.GFP.8 was used to establish a colony and was maintained on a C57BL/6J genetic background by the donating laboratory. 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 (Stock No. 000664).

Allele

Symbol: Tg(Ccr2-EGFP)8Pame
Name: transgene insertion 8, Eric G Pamer
MGI accession ID: MGI:4950277
Generation method: Transgenic
Attributes: Reporter
Synonyms: CCR2.GFP.8; Tg(Ccr2-GFP)8Pame
Marker symbol: Tg(Ccr2-EGFP)8Pame
Marker name: transgene insertion 8, Eric G Pamer
Chromosome: UN
Strain of origin: C57BL/6J
Molecular note: The transgene contains BAC clone RP23-182D4 with the insertion of EGFP with a stop codon between the first and second codon of the Ccr2 gene. Line 8 was generated.