FVB.Cg-Tg(SOD1*G85R/EYFP)641Alho/DboJ

Stock number: 035525
Product name: G85R-SOD1:YFP
Research areas: Mouse/Human Gene Homologs, Neurobiology Research, Research Tools

Description

These G85R SOD1-YFP transgenic mice express the human SOD1 (superoxide dismutase 1, soluble) gene bearing a G85R mutation fused to an EYFP reporter on the FVB/NJ background. Homozygous mice develop symptoms of Amyotrophic Lateral Sclerosis (ALS or Lou Gehrig's Disease) beginning at 9 months of age.

Detailed description

The G85R SOD1-YFP transgene expresses a human G85R mutant superoxide dismutase 1, soluble gene (SOD1) sequence fused to an EYFP reporter. SOD1 is a widely expressed isozyme responsible for destroying free superoxide radicals. SOD1 mutations, including SOD1*G85R, are known to cause amyotrophic lateral sclerosis (ALS) a motor neuron disease resulting in progressive paralysis.  The G85R mutation creates a misfolded protein that aggregates to form pathologoical inclusions. Mice homozygous for the transgene on the FVB/NJ background develop symptoms and pathology resembling human ALS beginning at 9 months of age, including protein aggregates in motor neuron cell bodies, GFAP reactivity and progressive paralysis. A subset of hemizygous mice develop ALS-like symptoms beginning at 20 months of age. G85R SOD1-YFP hemizygotes are viable and fertile. Injection of spinal homogenates from paralyzed mutant SOD1 mice into the sciatic nerves of adult G85R SOD1-YFP mice produces a prion-like propagation of motor neuron disease. Misfolded protein is observed first in the ipsilateral dorsal root ganglion, spreading to the lumbar spinal cord to the cervical cord and into the brainstem and midbrain. These G85R-SOD1 transgenic mice may be useful in studying neuromuscular disorders, including Amyotrophic Lateral Sclerosis (ALS or Lou Gehrig's Disease).

Development

The G85R SOD1-YFP transgene was created in the laboratory of Drs. Jiou Wang and Arthur Horwich at Yale University. The transgene was designed with a mutant human SOD1 (harboring a single amino acid substitution of glycine to arginine at amino acid 85 in exon IV; G85R) driven by its endogenous human promoter fused in frame at the last codon in exon V to the EYFP coding sequence. The linearized construct was microinjected into fertilized (C57BL/6J x SJL/J)F2 oocytes. Founder 641 carrying a single transgene insertion was maintained on a mixed background.  Mice from the colony were transferred to Dr. David Borchelt at the University of Florida and backcrossed to FVB/NJ for more than 10 generations. Upon arrival, mice were bred to FVB/NJ for at least 1 generation to establish the colony.

Note that the nomenclature refers to the G85R amino acid (aa) change in the 153 aa SOD1 protein (Wang et al. 2009 PNAS 106:1392 [PMID:19171884]), whereas the Ensembl transcript numbering consensus is an 154 aa SOD1 protein - thus predicting this mutation to be G86R. It is likely that the source of the numbering discrepancy is that the protein has cleaved off the N-terminal methionine (see Barra et al. 1980 FEBS Lett 120:53 [PMID:7002610]), whereas the genomic sequence database assumes the N-terminal methionine is still present.

Allele

Symbol: Tg(SOD1*G85R/EYFP)641Alho
Name: transgene insertion 641, Arthur L Horwich
MGI accession ID: MGI:5621057
Generation method: Transgenic
Attributes: Reporter; Inserted expressed sequence; Humanized sequence
Synonyms: G85R SOD-YFP
Marker symbol: Tg(SOD1*G85R/EYFP)641Alho
Marker name: transgene insertion 641, Arthur L Horwich
Marker synonyms: G85R SOD-YFP
Chromosome: UN
Strain of origin: (C57BL/6J x SJL/J)F2
Site of expression: widespread expression

Molecular note: A 12 kb genomic fragment of human SOD1 carrying the glycine to arginine substitution at amino acid 85 (G85R) fused to EYFP coding sequence through its C-terminal coding sequence in exon 5 was used as the transgene. The G85R mutation results in a misfolded protein associated with amyotrophic lateral sclerosis in humans and the mutant fusion protein behaves as a misfolded monomer. Southern blot analysis indicates that line 641 carries a single (multicopy) transgene insertion. In situ RNA hybridization indicates that the transgene is predominantly in motor neurons in the spinal cord.