B6.FVB-Tg(CAG-boNT/B,-EGFP)U75-56Fwp/J

Stock number: 018056
Research areas: Cell Biology Research, Research Tools

Description

iBot transgenic mice express an Clostridium botulinum neurotoxin serotype B light chain (boNT/B) gene in a cre-dependent fashion allowing selective blockage of calcium-dependent exocytosis.

Detailed description

These iBot transgenic mice contain a floxed-STOP cassette upstream of a Clostridium botulinum neurotoxin serotype B light chain (boNT/B) gene followed by an IRES-EGFP. A CAG promoter drives expression of the construct. Expression can be regulated by the presence of cre recombinase which would facilitate the excision the floxed-stop sequence. When translated, the boNT/B protein selectively blocks calcium-dependent exocytosis.

The boNT/B protein cleaves VAMP1 (vesicle-associated membrane protein 1), VAMP2 (vesicle-associated membrane protein 2, synaptobrevin 2) and VAMP3 (vesicle-associated membrane protein 3), preventing vesicle docking and release. Although botulinum neurotoxin is a potent neuroparalytic toxin, it is also used clinically for treatment of many neuromuscular diseases.

After Cre recombinase mediated excision of the STOP cassette, EGFP expression is detected by immunohistochemical staining, and co-expresses with the neurotoxin. Mice hemizygous for the transgenic insert are viable and fertile. The Donating Investigator has not attempted to make the strain homozygous.

When bred to a strain with widespread Cre recombinase expression, the bi-allelic progeny mice exhibit a perinatal lethal phenotype.

When bred to a strain with Cre recombinase expression in cerebellar neurons, this mutant mouse strain may be useful in studies of SNARE (soluble N-ethylmaleimide-sensitive factor-attachment protein receptor )-dependent synaptic transmission.

Development

A transgenic construct containing a floxed STOP cassette, Clostridium botulinum neurotoxin serotype B light chain (boNT/B), followed by IRES-EGFP, under the control of the CMV enhancer/chicken beta-actin promoter (CAG), was injected into fertilized FVB/N mouse eggs. Founder line U75-56 was subsequently established. The mice were then backcrossed to C57BL/6 for 10 generations. During backcrossing, the Y chromosome may not have been fixed to the C57BL/6J genetic background. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) at least once to establish the colony.

Allele

Symbol: Tg(CAG-boNT/B,-EGFP)U75-56Fwp
Name: transgene insertion U75-56, Frank W Pfrieger
MGI accession ID: MGI:5318975
Generation method: Transgenic
Attributes: Inserted expressed sequence
Marker symbol: Tg(CAG-boNT/B,-EGFP)U75-56Fwp
Marker name: transgene insertion U75-56, Frank W Pfrieger
Chromosome: UN
Strain of origin: FVB/N
Expressed genes: GFP,Green Fluorescent Protein,; boNT/B,botulinum neurotoxin serotype B light chain,clostridium
Site of expression: Cre excision of the stop signal results in botulinum neurotoxin and EGFP expression in cre-expressing tissues.
Molecular note: A CAG promoter followed by a floxed stop construct is attached to a clostridial botulinum neurotoxin serotype B light chain (BoNT/B) and IRES EGFP. Cre excision of the stop signal results in botulinum neurotoxin and EGFP expression.