B6.Cg-Tg(CAG-mRFP1)1F1Hadj/J

Stock number: 005884
Product name: CAG::mRFP1
Research areas: Research Tools

Description

These transgenic mice express red fluorescent protein under control of the chicken beta actin promoter and cytomegalovirus (CMV) enhancer in embryonic stem cells, embryos, and adults. This strain may be useful in studies of transplantation, embryo chimera experiments, and fluorescent imaging and technology development.

Detailed description

Mice homozygous for the CAG::mRFP1 transgene exhibit robust and widespread expression of monomeric red fluorescent protein-1 (mRFP1) in embryonic stem cells, embryos, and adults. Unlike tetrameric or dimeric fluorescent proteins, high levels of mRFP1 expression do not affect cell morphology, developmental potential, viability, and fertility of homozygous mice. Various optical imaging modalities can be used to visualize mRFP1 expressing cells in culture, in embryos and adult mice. Cells from transgenic mRFP1 mice, sampled along with green and cyan fluorescent cells from other mice, show clearly discernable fluorescence. This mouse may be useful in studies of mRFP1 cell lines, transplantation, embryo chimera experiments, and fluorescent imaging and technology development.

In February 2021, The Jackson Laboratory examined a cohort of CAG::mRFP1 hemizygous mice peripheral blood for flow cytometry analysis of RFP. This confirmed RFP expression in CAG::mRFP1 peripheral blood in the examined cell type, CD8+ T cells [view data].

In an attempt to offer alleles on well-characterized or multiple genetic backgrounds, alleles are frequently moved to a genetic background different from that on which an allele was first characterized. It should be noted that the phenotype could vary from that originally described. We will modify the strain description if necessary as published results become available.

Development

The first true monomeric red fluorescent protein (mRFP1) is the result of the stepwise directed evolution of DsRed; introducing 33 amino acid substitutions selecting for improved performance and developmental neutrality. The mRFP1 coding sequence was placed under control of the chicken beta actin promoter and CMV immediate early enhancer combination, designed to drive high-level constitutive gene expression in ES cells, embryos and adult mice. The construct (CAG-mRFP1) was injected into (129X1/SvJ x 129S1/Sv)F1-derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts and the resulting chimeras were bred to ICR. Founder line 1F1 was obtained and bred to ICR mice for five generations before arrival at The Jackson Laboratory. Upon arrival, this mouse was backcrossed to C57BL/6J mice for at least 5 generations.

Allele

Symbol: Tg(CAG-mRFP1)1F1Hadj
Name: transgene insertion 1F1, Anna-Katerina Hadjantonakis
MGI accession ID: MGI:3663356
Generation method: Transgenic
Attributes: Reporter
Marker symbol: Tg(CAG-mRFP1)1F1Hadj
Marker name: transgene insertion 1F1, Anna-Katerina Hadjantonakis
Chromosome: UN
Strain of origin: (129X1/SvJ x 129S1/Sv)F1-Kitl⁺
Expressed genes: RFP,Red Fluorescent Protein,coral
Site of expression: Robust and widespread expression of monomeric red fluorescent protein-1 (mRFP1) in embryonic stem cells, embryos, and adults. Unlike tetrameric or dimeric fluorescent proteins, high levels of mRFP1 expression do not affect cell morphology, developmental potential, viability, and fertility of homozygous mice.
Molecular note: The first true monomeric red fluorescent protein (mRFP1) is the result of the stepwise directed evolution of DsRed; introducing 33 amino acid substitutions selecting for improved performance and developmental neutrality. The mRFP1 coding sequence was placed under control of the chicken beta actin promoter and cytomegalovirus (CMV) immediate early enhancer combination, designed to drive high-level constitutive gene expression in ES cells, embryos and adult mice. The construct (CAG-mRFP1) was electroporated into (129X1/SvJ x 129S1/Sv)F1-derived R1 embryonic stem (ES) cells. Mice hemizygous for the transgene exhibit robust and widespread expression of monomeric red fluorescent protein-1 (mRFP1) in embryonic stem cells, embryos, and adults.